diff -r 000000000000 -r 6474c204b198 content/xul/templates/src/nsXULContentBuilder.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/xul/templates/src/nsXULContentBuilder.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,1988 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/ArrayUtils.h"
+
+#include "nsContentCID.h"
+#include "nsIDocument.h"
+#include "nsIDOMNodeList.h"
+#include "nsIDOMXULDocument.h"
+#include "nsINodeInfo.h"
+#include "nsIServiceManager.h"
+#include "nsIXULDocument.h"
+
+#include "nsContentSupportMap.h"
+#include "nsRDFConMemberTestNode.h"
+#include "nsRDFPropertyTestNode.h"
+#include "nsXULSortService.h"
+#include "nsTemplateRule.h"
+#include "nsTemplateMap.h"
+#include "nsTArray.h"
+#include "nsXPIDLString.h"
+#include "nsGkAtoms.h"
+#include "nsXULContentUtils.h"
+#include "nsXULElement.h"
+#include "nsXULTemplateBuilder.h"
+#include "nsNodeInfoManager.h"
+#include "nsContentCreatorFunctions.h"
+#include "nsContentUtils.h"
+#include "nsAttrName.h"
+#include "nsNodeUtils.h"
+#include "mozAutoDocUpdate.h"
+#include "nsTextNode.h"
+#include "mozilla/dom/Element.h"
+
+#include "pldhash.h"
+#include "rdf.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+//----------------------------------------------------------------------
+//
+// Return values for EnsureElementHasGenericChild()
+//
+#define NS_ELEMENT_GOT_CREATED NS_RDF_NO_VALUE
+#define NS_ELEMENT_WAS_THERE   NS_OK
+
+//----------------------------------------------------------------------
+//
+// nsXULContentBuilder
+//
+
+/**
+ * The content builder generates DOM nodes from a template. The actual content
+ * generation is done entirely inside BuildContentFromTemplate.
+ *
+ * Content generation is centered around the generation node (the node with
+ * uri="?member" on it). Nodes above the generation node are unique and
+ * generated only once. BuildContentFromTemplate will be passed the unique
+ * flag as an argument for content at this point and will recurse until it
+ * finds the generation node.
+ *
+ * Once the generation node has been found, the results for that content node
+ * are added to the content map, stored in mContentSupportMap.
+ *
+ * If recursion is allowed, generation continues, where the generation node
+ * becomes the container to insert into.
+ */
+class nsXULContentBuilder : public nsXULTemplateBuilder
+{
+public:
+    // nsIXULTemplateBuilder interface
+    NS_IMETHOD CreateContents(nsIContent* aElement, bool aForceCreation);
+
+    NS_IMETHOD HasGeneratedContent(nsIRDFResource* aResource,
+                                   nsIAtom* aTag,
+                                   bool* aGenerated);
+
+    NS_IMETHOD GetResultForContent(nsIDOMElement* aContent,
+                                   nsIXULTemplateResult** aResult);
+
+    // nsIMutationObserver interface
+    NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
+    NS_DECL_NSIMUTATIONOBSERVER_NODEWILLBEDESTROYED
+
+protected:
+    friend nsresult
+    NS_NewXULContentBuilder(nsISupports* aOuter, REFNSIID aIID, void** aResult);
+
+    nsXULContentBuilder();
+
+    void Traverse(nsCycleCollectionTraversalCallback &cb) const
+    {
+        mSortState.Traverse(cb);
+    }
+
+    virtual void Uninit(bool aIsFinal);
+
+    // Implementation methods
+    nsresult
+    OpenContainer(nsIContent* aElement);
+
+    nsresult
+    CloseContainer(nsIContent* aElement);
+
+    /**
+     * Build content from a template for a given result. This will be called
+     * recursively or on demand and will be called for every node in the
+     * generated content tree.
+     */
+    nsresult
+    BuildContentFromTemplate(nsIContent *aTemplateNode,
+                             nsIContent *aResourceNode,
+                             nsIContent *aRealNode,
+                             bool aIsUnique,
+                             bool aIsSelfReference,
+                             nsIXULTemplateResult* aChild,
+                             bool aNotify,
+                             nsTemplateMatch* aMatch,
+                             nsIContent** aContainer,
+                             int32_t* aNewIndexInContainer);
+
+    /**
+     * Copy the attributes from the template node to the node generated
+     * from it, performing any substitutions.
+     *
+     * @param aTemplateNode node within template
+     * @param aRealNode generated node to set attibutes upon
+     * @param aResult result to look up variable->value bindings in
+     * @param aNotify true to notify of DOM changes
+     */
+    nsresult
+    CopyAttributesToElement(nsIContent* aTemplateNode,
+                            nsIContent* aRealNode,
+                            nsIXULTemplateResult* aResult,
+                            bool aNotify);
+
+    /**
+     * Add any necessary persistent attributes (persist="...") from the
+     * local store to a generated node.
+     *
+     * @param aTemplateNode node within template
+     * @param aRealNode generated node to set persisted attibutes upon
+     * @param aResult result to look up variable->value bindings in
+     */
+    nsresult
+    AddPersistentAttributes(Element* aTemplateNode,
+                            nsIXULTemplateResult* aResult,
+                            nsIContent* aRealNode);
+
+    /**
+     * Recalculate any attributes that have variable references. This will
+     * be called when a binding has been changed to update the attributes.
+     * The attributes are copied from the node aTemplateNode in the template
+     * to the generated node aRealNode, using the values from the result
+     * aResult. This method will operate recursively.
+     *
+     * @param aTemplateNode node within template
+     * @param aRealNode generated node to set attibutes upon
+     * @param aResult result to look up variable->value bindings in
+     */
+    nsresult
+    SynchronizeUsingTemplate(nsIContent *aTemplateNode,
+                             nsIContent* aRealNode,
+                             nsIXULTemplateResult* aResult);
+
+    /**
+     * Remove the generated node aContent from the DOM and the hashtables
+     * used by the content builder.
+     */
+    nsresult
+    RemoveMember(nsIContent* aContent);
+
+    /**
+     * Create the appropriate generated content for aElement, by calling
+     * CreateContainerContents.
+     *
+     * @param aElement element to generate content inside
+     * @param aForceCreation true to force creation for closed items such as menus
+     */
+    nsresult
+    CreateTemplateAndContainerContents(nsIContent* aElement,
+                                       bool aForceCreation);
+
+    /**
+     * Generate the results for a template, by calling
+     * CreateContainerContentsForQuerySet for each queryset.
+     *
+     * @param aElement element to generate content inside
+     * @param aResult reference point for query
+     * @param aForceCreation true to force creation for closed items such as menus
+     * @param aNotify true to notify of DOM changes as each element is inserted
+     * @param aNotifyAtEnd notify at the end of all DOM changes
+     */
+    nsresult
+    CreateContainerContents(nsIContent* aElement,
+                            nsIXULTemplateResult* aResult,
+                            bool aForceCreation,
+                            bool aNotify,
+                            bool aNotifyAtEnd);
+
+    /**
+     * Generate the results for a query.
+     *
+     * @param aElement element to generate content inside
+     * @param aResult reference point for query
+     * @param aNotify true to notify of DOM changes
+     * @param aContainer container content was added inside
+     * @param aNewIndexInContainer index with container in which content was added
+     */
+    nsresult
+    CreateContainerContentsForQuerySet(nsIContent* aElement,
+                                       nsIXULTemplateResult* aResult,
+                                       bool aNotify,
+                                       nsTemplateQuerySet* aQuerySet,
+                                       nsIContent** aContainer,
+                                       int32_t* aNewIndexInContainer);
+
+    /**
+     * Check if an element with a particular tag exists with a container.
+     * If it is not present, append a new element with that tag into the
+     * container.
+     *
+     * @param aParent parent container
+     * @param aNameSpaceID namespace of tag to locate or create
+     * @param aTag tag to locate or create
+     * @param aNotify true to notify of DOM changes
+     * @param aResult set to the found or created node.
+     */
+    nsresult
+    EnsureElementHasGenericChild(nsIContent* aParent,
+                                 int32_t aNameSpaceID,
+                                 nsIAtom* aTag,
+                                 bool aNotify,
+                                 nsIContent** aResult);
+
+    bool
+    IsOpen(nsIContent* aElement);
+
+    nsresult
+    RemoveGeneratedContent(nsIContent* aElement);
+
+    nsresult
+    GetElementsForResult(nsIXULTemplateResult* aResult,
+                         nsCOMArray<nsIContent>& aElements);
+
+    nsresult
+    CreateElement(int32_t aNameSpaceID,
+                  nsIAtom* aTag,
+                  Element** aResult);
+
+    /**
+     * Set the container and empty attributes on a node. If
+     * aIgnoreNonContainers is true, then the element is not changed
+     * for non-containers. Otherwise, the container attribute will be set to
+     * false.
+     *
+     * @param aElement element to set attributes on
+     * @param aResult result to use to determine state of attributes
+     * @param aIgnoreNonContainers true to not change for non-containers
+     * @param aNotify true to notify of DOM changes
+     */
+    nsresult
+    SetContainerAttrs(nsIContent *aElement,
+                      nsIXULTemplateResult* aResult,
+                      bool aIgnoreNonContainers,
+                      bool aNotify);
+
+    virtual nsresult
+    RebuildAll();
+
+    // GetInsertionLocations, ReplaceMatch and SynchronizeResult are inherited
+    // from nsXULTemplateBuilder
+
+    /**
+     * Return true if the result can be inserted into the template as
+     * generated content. For the content builder, aLocations will be set
+     * to the list of containers where the content should be inserted.
+     */
+    virtual bool
+    GetInsertionLocations(nsIXULTemplateResult* aOldResult,
+                          nsCOMArray<nsIContent>** aLocations);
+
+    /**
+     * Remove the content associated with aOldResult which no longer matches,
+     * and/or generate content for a new match.
+     */
+    virtual nsresult
+    ReplaceMatch(nsIXULTemplateResult* aOldResult,
+                 nsTemplateMatch* aNewMatch,
+                 nsTemplateRule* aNewMatchRule,
+                 void *aContext);
+
+    /**
+     * Synchronize a result bindings with the generated content for that
+     * result. This will be called as a result of the template builder's
+     * ResultBindingChanged method.
+     */
+    virtual nsresult
+    SynchronizeResult(nsIXULTemplateResult* aResult);
+
+    /**
+     * Compare a result to a content node. If the generated content for the
+     * result should come before aContent, set aSortOrder to -1. If it should
+     * come after, set sortOrder to 1. If both are equal, set to 0.
+     */
+    nsresult
+    CompareResultToNode(nsIXULTemplateResult* aResult, nsIContent* aContent,
+                        int32_t* aSortOrder);
+
+    /**
+     * Insert a generated node into the container where it should go according
+     * to the current sort. aNode is the generated content node and aResult is
+     * the result for the generated node.
+     */
+    nsresult
+    InsertSortedNode(nsIContent* aContainer,
+                     nsIContent* aNode,
+                     nsIXULTemplateResult* aResult,
+                     bool aNotify);
+
+    /**
+     * Maintains a mapping between elements in the DOM and the matches
+     * that they support.
+     */
+    nsContentSupportMap mContentSupportMap;
+
+    /**
+     * Maintains a mapping from an element in the DOM to the template
+     * element that it was created from.
+     */
+    nsTemplateMap mTemplateMap;
+
+    /**
+     * Information about the currently active sort
+     */
+    nsSortState mSortState;
+};
+
+nsresult
+NS_NewXULContentBuilder(nsISupports* aOuter, REFNSIID aIID, void** aResult)
+{
+    NS_PRECONDITION(aOuter == nullptr, "no aggregation");
+    if (aOuter)
+        return NS_ERROR_NO_AGGREGATION;
+
+    nsresult rv;
+    nsXULContentBuilder* result = new nsXULContentBuilder();
+    if (!result)
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    NS_ADDREF(result); // stabilize
+
+    rv = result->InitGlobals();
+
+    if (NS_SUCCEEDED(rv))
+        rv = result->QueryInterface(aIID, aResult);
+
+    NS_RELEASE(result);
+    return rv;
+}
+
+nsXULContentBuilder::nsXULContentBuilder()
+{
+  mSortState.initialized = false;
+}
+
+void
+nsXULContentBuilder::Uninit(bool aIsFinal)
+{
+    if (! aIsFinal && mRoot) {
+        nsresult rv = RemoveGeneratedContent(mRoot);
+        if (NS_FAILED(rv))
+            return;
+    }
+
+    // Nuke the content support map completely.
+    mContentSupportMap.Clear();
+    mTemplateMap.Clear();
+
+    mSortState.initialized = false;
+
+    nsXULTemplateBuilder::Uninit(aIsFinal);
+}
+
+nsresult
+nsXULContentBuilder::BuildContentFromTemplate(nsIContent *aTemplateNode,
+                                              nsIContent *aResourceNode,
+                                              nsIContent *aRealNode,
+                                              bool aIsUnique,
+                                              bool aIsSelfReference,
+                                              nsIXULTemplateResult* aChild,
+                                              bool aNotify,
+                                              nsTemplateMatch* aMatch,
+                                              nsIContent** aContainer,
+                                              int32_t* aNewIndexInContainer)
+{
+    // This is the mother lode. Here is where we grovel through an
+    // element in the template, copying children from the template
+    // into the "real" content tree, performing substitution as we go
+    // by looking stuff up using the results.
+    //
+    //   |aTemplateNode| is the element in the "template tree", whose
+    //   children we will duplicate and move into the "real" content
+    //   tree.
+    //
+    //   |aResourceNode| is the element in the "real" content tree that
+    //   has the "id" attribute set to an result's id. This is
+    //   not directly used here, but rather passed down to the XUL
+    //   sort service to perform container-level sort.
+    //
+    //   |aRealNode| is the element in the "real" content tree to which
+    //   the new elements will be copied.
+    //
+    //   |aIsUnique| is set to "true" so long as content has been
+    //   "unique" (or "above" the resource element) so far in the
+    //   template.
+    //
+    //   |aIsSelfReference| should be set to "true" for cases where
+    //   the reference and member variables are the same, indicating
+    //   that the generated node is the same as the reference point,
+    //   so generation should not recurse, or else an infinite loop
+    //   would occur.
+    //
+    //   |aChild| is the result for which we are building content.
+    //
+    //   |aNotify| is set to "true" if content should be constructed
+    //   "noisily"; that is, whether the document observers should be
+    //   notified when new content is added to the content model.
+    //
+    //   |aContainer| is an out parameter that will be set to the first
+    //   container element in the "real" content tree to which content
+    //   was appended.
+    //
+    //   |aNewIndexInContainer| is an out parameter that will be set to
+    //   the index in aContainer at which new content is first
+    //   constructed.
+    //
+    // If |aNotify| is "false", then |aContainer| and
+    // |aNewIndexInContainer| are used to determine where in the
+    // content model new content is constructed. This allows a single
+    // notification to be propagated to document observers.
+    //
+
+    nsresult rv;
+
+#ifdef PR_LOGGING
+    if (PR_LOG_TEST(gXULTemplateLog, PR_LOG_DEBUG)) {
+        PR_LOG(gXULTemplateLog, PR_LOG_ALWAYS,
+               ("nsXULContentBuilder::BuildContentFromTemplate (is unique: %d)",
+               aIsUnique));
+
+        nsAutoString id;
+        aChild->GetId(id);
+
+        PR_LOG(gXULTemplateLog, PR_LOG_ALWAYS,
+               ("Tags: [Template: %s  Resource: %s  Real: %s] for id %s",
+                nsAtomCString(aTemplateNode->Tag()).get(), 
+                nsAtomCString(aResourceNode->Tag()).get(),
+                nsAtomCString(aRealNode->Tag()).get(), NS_ConvertUTF16toUTF8(id).get()));
+    }
+#endif
+
+    // Iterate through all of the template children, constructing
+    // "real" content model nodes for each "template" child.
+    for (nsIContent* tmplKid = aTemplateNode->GetFirstChild();
+         tmplKid;
+         tmplKid = tmplKid->GetNextSibling()) {
+
+        int32_t nameSpaceID = tmplKid->GetNameSpaceID();
+
+        // Check whether this element is the generation element. The generation
+        // element is the element that is cookie-cutter copied once for each
+        // different result specified by |aChild|.
+        //
+        // Nodes that appear -above- the generation element
+        // (that is, are ancestors of the generation element in the
+        // content model) are unique across all values of |aChild|,
+        // and are created only once.
+        //
+        // Nodes that appear -below- the generation element (that is,
+        // are descendants of the generation element in the content
+        // model), are cookie-cutter copied for each distinct value of
+        // |aChild|.
+        //
+        // For example, in a <tree> template:
+        //
+        //   <tree>
+        //     <template>
+        //       <treechildren> [1]
+        //         <treeitem uri="rdf:*"> [2]
+        //           <treerow> [3]
+        //             <treecell value="rdf:urn:foo" /> [4]
+        //             <treecell value="rdf:urn:bar" /> [5]
+        //           </treerow>
+        //         </treeitem>
+        //       </treechildren>
+        //     </template>
+        //   </tree>
+        //
+        // The <treeitem> element [2] is the generation element. This
+        // element, and all of its descendants ([3], [4], and [5])
+        // will be duplicated for each different |aChild|.
+        // It's ancestor <treechildren> [1] is unique, and
+        // will only be created -once-, no matter how many <treeitem>s
+        // are created below it.
+        //
+        // isUnique will be true for nodes above the generation element,
+        // isGenerationElement will be true for the generation element,
+        // and both will be false for descendants
+        bool isGenerationElement = false;
+        bool isUnique = aIsUnique;
+
+        // We identify the resource element by presence of a
+        // "uri='rdf:*'" attribute. (We also support the older
+        // "uri='...'" syntax.)
+        if (tmplKid->HasAttr(kNameSpaceID_None, nsGkAtoms::uri) && aMatch->IsActive()) {
+            isGenerationElement = true;
+            isUnique = false;
+        }
+
+        MOZ_ASSERT_IF(isGenerationElement, tmplKid->IsElement());
+
+        nsIAtom *tag = tmplKid->Tag();
+
+#ifdef PR_LOGGING
+        if (PR_LOG_TEST(gXULTemplateLog, PR_LOG_DEBUG)) {
+            PR_LOG(gXULTemplateLog, PR_LOG_DEBUG,
+                   ("xultemplate[%p]     building %s %s %s",
+                    this, nsAtomCString(tag).get(),
+                    (isGenerationElement ? "[resource]" : ""),
+                    (isUnique ? "[unique]" : "")));
+        }
+#endif
+
+        // Set to true if the child we're trying to create now
+        // already existed in the content model.
+        bool realKidAlreadyExisted = false;
+
+        nsCOMPtr<nsIContent> realKid;
+        if (isUnique) {
+            // The content is "unique"; that is, we haven't descended
+            // far enough into the template to hit the generation
+            // element yet. |EnsureElementHasGenericChild()| will
+            // conditionally create the element iff it isn't there
+            // already.
+            rv = EnsureElementHasGenericChild(aRealNode, nameSpaceID, tag, aNotify, getter_AddRefs(realKid));
+            if (NS_FAILED(rv))
+                return rv;
+
+            if (rv == NS_ELEMENT_WAS_THERE) {
+                realKidAlreadyExisted = true;
+            }
+            else {
+                // Potentially remember the index of this element as the first
+                // element that we've generated. Note that we remember
+                // this -before- we recurse!
+                if (aContainer && !*aContainer) {
+                    *aContainer = aRealNode;
+                    NS_ADDREF(*aContainer);
+
+                    uint32_t indx = aRealNode->GetChildCount();
+
+                    // Since EnsureElementHasGenericChild() added us, make
+                    // sure to subtract one for our real index.
+                    *aNewIndexInContainer = indx - 1;
+                }
+            }
+
+            // Recurse until we get to the resource element. Since
+            // -we're- unique, assume that our child will be
+            // unique. The check for the "resource" element at the top
+            // of the function will trip this to |false| as soon as we
+            // encounter it.
+            rv = BuildContentFromTemplate(tmplKid, aResourceNode, realKid, true,
+                                          aIsSelfReference, aChild, aNotify, aMatch,
+                                          aContainer, aNewIndexInContainer);
+
+            if (NS_FAILED(rv))
+                return rv;
+        }
+        else if (isGenerationElement) {
+            // It's the "resource" element. Create a new element using
+            // the namespace ID and tag from the template element.
+            nsCOMPtr<Element> element;
+            rv = CreateElement(nameSpaceID, tag, getter_AddRefs(element));
+            if (NS_FAILED(rv))
+                return rv;
+            realKid = element.forget();
+
+            // Add the resource element to the content support map so
+            // we can remove the match based on the content node later.
+            mContentSupportMap.Put(realKid, aMatch);
+
+            // Assign the element an 'id' attribute using result's id
+            nsAutoString id;
+            rv = aChild->GetId(id);
+            if (NS_FAILED(rv))
+                return rv;
+
+            rv = realKid->SetAttr(kNameSpaceID_None, nsGkAtoms::id, id, false);
+            if (NS_FAILED(rv))
+                return rv;
+
+            // Set up the element's 'container' and 'empty' attributes.
+            SetContainerAttrs(realKid, aChild, true, false);
+        }
+        else if (tag == nsGkAtoms::textnode &&
+                 nameSpaceID == kNameSpaceID_XUL) {
+            // <xul:text value="..."> is replaced by text of the
+            // actual value of the 'rdf:resource' attribute for the
+            // given node.
+            // SynchronizeUsingTemplate contains code used to update textnodes,
+            // so make sure to modify both when changing this
+            char16_t attrbuf[128];
+            nsFixedString attrValue(attrbuf, ArrayLength(attrbuf), 0);
+            tmplKid->GetAttr(kNameSpaceID_None, nsGkAtoms::value, attrValue);
+            if (!attrValue.IsEmpty()) {
+                nsAutoString value;
+                rv = SubstituteText(aChild, attrValue, value);
+                if (NS_FAILED(rv)) return rv;
+
+                nsRefPtr<nsTextNode> content =
+                  new nsTextNode(mRoot->NodeInfo()->NodeInfoManager());
+
+                content->SetText(value, false);
+
+                rv = aRealNode->AppendChildTo(content, aNotify);
+                if (NS_FAILED(rv)) return rv;
+
+                // XXX Don't bother remembering text nodes as the
+                // first element we've generated?
+            }
+        }
+        else if (tmplKid->IsNodeOfType(nsINode::eTEXT)) {
+            nsCOMPtr<nsIDOMNode> tmplTextNode = do_QueryInterface(tmplKid);
+            if (!tmplTextNode) {
+                NS_ERROR("textnode not implementing nsIDOMNode??");
+                return NS_ERROR_FAILURE;
+            }
+            nsCOMPtr<nsIDOMNode> clonedNode;
+            tmplTextNode->CloneNode(false, 1, getter_AddRefs(clonedNode));
+            nsCOMPtr<nsIContent> clonedContent = do_QueryInterface(clonedNode);
+            if (!clonedContent) {
+                NS_ERROR("failed to clone textnode");
+                return NS_ERROR_FAILURE;
+            }
+            rv = aRealNode->AppendChildTo(clonedContent, aNotify);
+            if (NS_FAILED(rv)) return rv;
+        }
+        else {
+            // It's just a generic element. Create it!
+            nsCOMPtr<Element> element;
+            rv = CreateElement(nameSpaceID, tag, getter_AddRefs(element));
+            if (NS_FAILED(rv)) return rv;
+            realKid = element.forget();
+        }
+
+        if (realKid && !realKidAlreadyExisted) {
+            // Potentially remember the index of this element as the
+            // first element that we've generated.
+            if (aContainer && !*aContainer) {
+                *aContainer = aRealNode;
+                NS_ADDREF(*aContainer);
+
+                uint32_t indx = aRealNode->GetChildCount();
+
+                // Since we haven't inserted any content yet, our new
+                // index in the container will be the current count of
+                // elements in the container.
+                *aNewIndexInContainer = indx;
+            }
+
+            // Remember the template kid from which we created the
+            // real kid. This allows us to sync back up with the
+            // template to incrementally build content.
+            mTemplateMap.Put(realKid, tmplKid);
+
+            rv = CopyAttributesToElement(tmplKid, realKid, aChild, false);
+            if (NS_FAILED(rv)) return rv;
+
+            // Add any persistent attributes
+            if (isGenerationElement) {
+                rv = AddPersistentAttributes(tmplKid->AsElement(), aChild,
+                                             realKid);
+                if (NS_FAILED(rv)) return rv;
+            }
+
+            // the unique content recurses up above. Also, don't recurse if
+            // this is a self reference (a reference to the same resource)
+            // or we'll end up regenerating the same content.
+            if (!aIsSelfReference && !isUnique) {
+                // this call creates the content inside the generation node,
+                // for example the label below:
+                //  <vbox uri="?">
+                //    <label value="?title"/>
+                //  </vbox>
+                rv = BuildContentFromTemplate(tmplKid, aResourceNode, realKid, false,
+                                              false, aChild, false, aMatch,
+                                              nullptr /* don't care */,
+                                              nullptr /* don't care */);
+                if (NS_FAILED(rv)) return rv;
+
+                if (isGenerationElement) {
+                    // build the next level of children
+                    rv = CreateContainerContents(realKid, aChild, false,
+                                                 false, false);
+                    if (NS_FAILED(rv)) return rv;
+                }
+            }
+
+            // We'll _already_ have added the unique elements; but if
+            // it's -not- unique, then use the XUL sort service now to
+            // append the element to the content model.
+            if (! isUnique) {
+                rv = NS_ERROR_UNEXPECTED;
+
+                if (isGenerationElement)
+                    rv = InsertSortedNode(aRealNode, realKid, aChild, aNotify);
+
+                if (NS_FAILED(rv)) {
+                    rv = aRealNode->AppendChildTo(realKid, aNotify);
+                    NS_ASSERTION(NS_SUCCEEDED(rv), "unable to insert element");
+                }
+            }
+        }
+    }
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CopyAttributesToElement(nsIContent* aTemplateNode,
+                                             nsIContent* aRealNode,
+                                             nsIXULTemplateResult* aResult,
+                                             bool aNotify)
+{
+    nsresult rv;
+
+    // Copy all attributes from the template to the new element
+    uint32_t numAttribs = aTemplateNode->GetAttrCount();
+
+    for (uint32_t attr = 0; attr < numAttribs; attr++) {
+        const nsAttrName* name = aTemplateNode->GetAttrNameAt(attr);
+        int32_t attribNameSpaceID = name->NamespaceID();
+        // Hold a strong reference here so that the atom doesn't go away
+        // during UnsetAttr.
+        nsCOMPtr<nsIAtom> attribName = name->LocalName();
+
+        // XXXndeakin ignore namespaces until bug 321182 is fixed
+        if (attribName != nsGkAtoms::id && attribName != nsGkAtoms::uri) {
+            // Create a buffer here, because there's a chance that an
+            // attribute in the template is going to be an RDF URI, which is
+            // usually longish.
+            char16_t attrbuf[128];
+            nsFixedString attribValue(attrbuf, ArrayLength(attrbuf), 0);
+            aTemplateNode->GetAttr(attribNameSpaceID, attribName, attribValue);
+            if (!attribValue.IsEmpty()) {
+                nsAutoString value;
+                rv = SubstituteText(aResult, attribValue, value);
+                if (NS_FAILED(rv))
+                    return rv;
+
+                // if the string is empty after substitutions, remove the
+                // attribute
+                if (!value.IsEmpty()) {
+                    rv = aRealNode->SetAttr(attribNameSpaceID,
+                                            attribName,
+                                            name->GetPrefix(),
+                                            value,
+                                            aNotify);
+                }
+                else {
+                    rv = aRealNode->UnsetAttr(attribNameSpaceID,
+                                              attribName,
+                                              aNotify);
+                }
+
+                if (NS_FAILED(rv))
+                    return rv;
+            }
+        }
+    }
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::AddPersistentAttributes(Element* aTemplateNode,
+                                             nsIXULTemplateResult* aResult,
+                                             nsIContent* aRealNode)
+{
+    if (!mRoot)
+        return NS_OK;
+
+    nsCOMPtr<nsIRDFResource> resource;
+    nsresult rv = GetResultResource(aResult, getter_AddRefs(resource));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsAutoString attribute, persist;
+    aTemplateNode->GetAttr(kNameSpaceID_None, nsGkAtoms::persist, persist);
+
+    while (!persist.IsEmpty()) {
+        attribute.Truncate();
+
+        int32_t offset = persist.FindCharInSet(" ,");
+        if (offset > 0) {
+            persist.Left(attribute, offset);
+            persist.Cut(0, offset + 1);
+        }
+        else {
+            attribute = persist;
+            persist.Truncate();
+        }
+
+        attribute.Trim(" ");
+
+        if (attribute.IsEmpty())
+            break;
+
+        nsCOMPtr<nsIAtom> tag;
+        int32_t nameSpaceID;
+
+        nsCOMPtr<nsINodeInfo> ni =
+            aTemplateNode->GetExistingAttrNameFromQName(attribute);
+        if (ni) {
+            tag = ni->NameAtom();
+            nameSpaceID = ni->NamespaceID();
+        }
+        else {
+            tag = do_GetAtom(attribute);
+            NS_ENSURE_TRUE(tag, NS_ERROR_OUT_OF_MEMORY);
+
+            nameSpaceID = kNameSpaceID_None;
+        }
+
+        nsCOMPtr<nsIRDFResource> property;
+        rv = nsXULContentUtils::GetResource(nameSpaceID, tag, getter_AddRefs(property));
+        NS_ENSURE_SUCCESS(rv, rv);
+
+        nsCOMPtr<nsIRDFNode> target;
+        rv = mDB->GetTarget(resource, property, true, getter_AddRefs(target));
+        NS_ENSURE_SUCCESS(rv, rv);
+
+        if (! target)
+            continue;
+
+        nsCOMPtr<nsIRDFLiteral> value = do_QueryInterface(target);
+        NS_ASSERTION(value != nullptr, "unable to stomach that sort of node");
+        if (! value)
+            continue;
+
+        const char16_t* valueStr;
+        rv = value->GetValueConst(&valueStr);
+        NS_ENSURE_SUCCESS(rv, rv);
+
+        rv = aRealNode->SetAttr(nameSpaceID, tag, nsDependentString(valueStr),
+                                false);
+        NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::SynchronizeUsingTemplate(nsIContent* aTemplateNode,
+                                              nsIContent* aRealElement,
+                                              nsIXULTemplateResult* aResult)
+{
+    // check all attributes on the template node; if they reference a resource,
+    // update the equivalent attribute on the content node
+    nsresult rv;
+    rv = CopyAttributesToElement(aTemplateNode, aRealElement, aResult, true);
+    if (NS_FAILED(rv))
+        return rv;
+
+    uint32_t count = aTemplateNode->GetChildCount();
+
+    for (uint32_t loop = 0; loop < count; ++loop) {
+        nsIContent *tmplKid = aTemplateNode->GetChildAt(loop);
+
+        if (! tmplKid)
+            break;
+
+        nsIContent *realKid = aRealElement->GetChildAt(loop);
+        if (! realKid)
+            break;
+
+        // check for text nodes and update them accordingly.
+        // This code is similar to that in BuildContentFromTemplate
+        if (tmplKid->NodeInfo()->Equals(nsGkAtoms::textnode,
+                                        kNameSpaceID_XUL)) {
+            char16_t attrbuf[128];
+            nsFixedString attrValue(attrbuf, ArrayLength(attrbuf), 0);
+            tmplKid->GetAttr(kNameSpaceID_None, nsGkAtoms::value, attrValue);
+            if (!attrValue.IsEmpty()) {
+                nsAutoString value;
+                rv = SubstituteText(aResult, attrValue, value);
+                if (NS_FAILED(rv)) return rv;
+                realKid->SetText(value, true);
+            }
+        }
+
+        rv = SynchronizeUsingTemplate(tmplKid, realKid, aResult);
+        if (NS_FAILED(rv)) return rv;
+    }
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::RemoveMember(nsIContent* aContent)
+{
+    nsCOMPtr<nsIContent> parent = aContent->GetParent();
+    if (parent) {
+        int32_t pos = parent->IndexOf(aContent);
+
+        NS_ASSERTION(pos >= 0, "parent doesn't think this child has an index");
+        if (pos < 0) return NS_OK;
+
+        // Note: RemoveChildAt sets |child|'s document to null so that
+        // it'll get knocked out of the XUL doc's resource-to-element
+        // map.
+        parent->RemoveChildAt(pos, true);
+    }
+
+    // Remove from the content support map.
+    mContentSupportMap.Remove(aContent);
+
+    // Remove from the template map
+    mTemplateMap.Remove(aContent);
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CreateTemplateAndContainerContents(nsIContent* aElement,
+                                                        bool aForceCreation)
+{
+    // Generate both 1) the template content for the current element,
+    // and 2) recursive subcontent (if the current element refers to a
+    // container result).
+
+    PR_LOG(gXULTemplateLog, PR_LOG_ALWAYS,
+           ("nsXULContentBuilder::CreateTemplateAndContainerContents start - flags: %d",
+            mFlags));
+
+    if (! mQueryProcessor)
+        return NS_OK;
+
+    // for the root element, get the ref attribute and generate content
+    if (aElement == mRoot) {
+        if (! mRootResult) {
+            nsAutoString ref;
+            mRoot->GetAttr(kNameSpaceID_None, nsGkAtoms::ref, ref);
+
+            if (! ref.IsEmpty()) {
+                nsresult rv = mQueryProcessor->TranslateRef(mDataSource, ref,
+                                                            getter_AddRefs(mRootResult));
+                if (NS_FAILED(rv))
+                    return rv;
+            }
+        }
+
+        if (mRootResult) {
+            CreateContainerContents(aElement, mRootResult, aForceCreation,
+                                    false, true);
+        }
+    }
+    else if (!(mFlags & eDontRecurse)) {
+        // The content map will contain the generation elements (the ones that
+        // are given ids) and only those elements, so get the reference point
+        // from the corresponding match.
+        nsTemplateMatch *match = nullptr;
+        if (mContentSupportMap.Get(aElement, &match))
+            CreateContainerContents(aElement, match->mResult, aForceCreation,
+                                    false, true);
+    }
+
+    PR_LOG(gXULTemplateLog, PR_LOG_ALWAYS,
+           ("nsXULContentBuilder::CreateTemplateAndContainerContents end"));
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CreateContainerContents(nsIContent* aElement,
+                                             nsIXULTemplateResult* aResult,
+                                             bool aForceCreation,
+                                             bool aNotify,
+                                             bool aNotifyAtEnd)
+{
+    if (!aForceCreation && !IsOpen(aElement))
+        return NS_OK;
+
+    // don't generate children if recursion or child processing isn't allowed
+    if (aResult != mRootResult) {
+        if (mFlags & eDontRecurse)
+            return NS_OK;
+
+        bool mayProcessChildren;
+        nsresult rv = aResult->GetMayProcessChildren(&mayProcessChildren);
+        if (NS_FAILED(rv) || !mayProcessChildren)
+            return rv;
+    }
+
+    nsCOMPtr<nsIRDFResource> refResource;
+    GetResultResource(aResult, getter_AddRefs(refResource));
+    if (! refResource)
+        return NS_ERROR_FAILURE;
+
+    // Avoid re-entrant builds for the same resource.
+    if (IsActivated(refResource))
+        return NS_OK;
+
+    ActivationEntry entry(refResource, &mTop);
+
+    // Compile the rules now, if they haven't been already.
+    if (! mQueriesCompiled) {
+        nsresult rv = CompileQueries();
+        if (NS_FAILED(rv))
+            return rv;
+    }
+
+    if (mQuerySets.Length() == 0)
+        return NS_OK;
+
+    // See if the element's templates contents have been generated:
+    // this prevents a re-entrant call from triggering another
+    // generation.
+    nsXULElement *xulcontent = nsXULElement::FromContent(aElement);
+    if (xulcontent) {
+        if (xulcontent->GetTemplateGenerated())
+            return NS_OK;
+
+        // Now mark the element's contents as being generated so that
+        // any re-entrant calls don't trigger an infinite recursion.
+        xulcontent->SetTemplateGenerated();
+    }
+
+    int32_t newIndexInContainer = -1;
+    nsIContent* container = nullptr;
+
+    int32_t querySetCount = mQuerySets.Length();
+
+    for (int32_t r = 0; r < querySetCount; r++) {
+        nsTemplateQuerySet* queryset = mQuerySets[r];
+
+        nsIAtom* tag = queryset->GetTag();
+        if (tag && tag != aElement->Tag())
+            continue;
+
+        CreateContainerContentsForQuerySet(aElement, aResult, aNotify, queryset,
+                                           &container, &newIndexInContainer);
+    }
+
+    if (aNotifyAtEnd && container) {
+        MOZ_AUTO_DOC_UPDATE(container->GetCurrentDoc(), UPDATE_CONTENT_MODEL,
+                            true);
+        nsNodeUtils::ContentAppended(container,
+                                     container->GetChildAt(newIndexInContainer),
+                                     newIndexInContainer);
+    }
+
+    NS_IF_RELEASE(container);
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CreateContainerContentsForQuerySet(nsIContent* aElement,
+                                                        nsIXULTemplateResult* aResult,
+                                                        bool aNotify,
+                                                        nsTemplateQuerySet* aQuerySet,
+                                                        nsIContent** aContainer,
+                                                        int32_t* aNewIndexInContainer)
+{
+#ifdef PR_LOGGING
+    if (PR_LOG_TEST(gXULTemplateLog, PR_LOG_DEBUG)) {
+        nsAutoString id;
+        aResult->GetId(id);
+        PR_LOG(gXULTemplateLog, PR_LOG_ALWAYS,
+               ("nsXULContentBuilder::CreateContainerContentsForQuerySet start for ref %s\n",
+               NS_ConvertUTF16toUTF8(id).get()));
+    }
+#endif
+
+    if (! mQueryProcessor)
+        return NS_OK;
+
+    nsCOMPtr<nsISimpleEnumerator> results;
+    nsresult rv = mQueryProcessor->GenerateResults(mDataSource, aResult,
+                                                   aQuerySet->mCompiledQuery,
+                                                   getter_AddRefs(results));
+    if (NS_FAILED(rv) || !results)
+        return rv;
+
+    bool hasMoreResults;
+    rv = results->HasMoreElements(&hasMoreResults);
+
+    for (; NS_SUCCEEDED(rv) && hasMoreResults;
+           rv = results->HasMoreElements(&hasMoreResults)) {
+        nsCOMPtr<nsISupports> nr;
+        rv = results->GetNext(getter_AddRefs(nr));
+        if (NS_FAILED(rv))
+            return rv;
+
+        nsCOMPtr<nsIXULTemplateResult> nextresult = do_QueryInterface(nr);
+        if (!nextresult)
+            return NS_ERROR_UNEXPECTED;
+
+        nsCOMPtr<nsIRDFResource> resultid;
+        rv = GetResultResource(nextresult, getter_AddRefs(resultid));
+        if (NS_FAILED(rv))
+            return rv;
+
+        if (!resultid)
+            continue;
+
+        nsTemplateMatch *newmatch =
+            nsTemplateMatch::Create(aQuerySet->Priority(),
+                                    nextresult, aElement);
+        if (!newmatch)
+            return NS_ERROR_OUT_OF_MEMORY;
+
+        // check if there is already an existing match. If so, a previous
+        // query already generated content so the match is just added to the
+        // end of the set of matches.
+
+        bool generateContent = true;
+
+        nsTemplateMatch* prevmatch = nullptr;
+        nsTemplateMatch* existingmatch = nullptr;
+        nsTemplateMatch* removematch = nullptr;
+        if (mMatchMap.Get(resultid, &existingmatch)){
+            // check if there is an existing match that matched a rule
+            while (existingmatch) {
+                // break out once we've reached a query in the list with a
+                // higher priority, as the new match list is sorted by
+                // priority, and the new match should be inserted here
+                int32_t priority = existingmatch->QuerySetPriority();
+                if (priority > aQuerySet->Priority())
+                    break;
+
+                // skip over non-matching containers 
+                if (existingmatch->GetContainer() == aElement) {
+                    // if the same priority is already found, replace it. This can happen
+                    // when a container is removed and readded
+                    if (priority == aQuerySet->Priority()) {
+                        removematch = existingmatch;
+                        break;
+                    }
+
+                    if (existingmatch->IsActive())
+                        generateContent = false;
+                }
+
+                prevmatch = existingmatch;
+                existingmatch = existingmatch->mNext;
+            }
+        }
+
+        if (removematch) {
+            // remove the generated content for the existing match
+            rv = ReplaceMatch(removematch->mResult, nullptr, nullptr, aElement);
+            if (NS_FAILED(rv))
+                return rv;
+
+            if (mFlags & eLoggingEnabled)
+                OutputMatchToLog(resultid, removematch, false);
+        }
+
+        if (generateContent) {
+            // find the rule that matches. If none match, the content does not
+            // need to be generated
+
+            int16_t ruleindex;
+            nsTemplateRule* matchedrule = nullptr;
+            rv = DetermineMatchedRule(aElement, nextresult, aQuerySet,
+                                      &matchedrule, &ruleindex);
+            if (NS_FAILED(rv)) {
+                nsTemplateMatch::Destroy(newmatch, false);
+                return rv;
+            }
+
+            if (matchedrule) {
+                rv = newmatch->RuleMatched(aQuerySet, matchedrule,
+                                           ruleindex, nextresult);
+                if (NS_FAILED(rv)) {
+                    nsTemplateMatch::Destroy(newmatch, false);
+                    return rv;
+                }
+
+                // Grab the template node
+                nsCOMPtr<nsIContent> action = matchedrule->GetAction();
+                BuildContentFromTemplate(action, aElement, aElement, true,
+                                         mRefVariable == matchedrule->GetMemberVariable(),
+                                         nextresult, aNotify, newmatch,
+                                         aContainer, aNewIndexInContainer);
+            }
+        }
+
+        if (mFlags & eLoggingEnabled)
+            OutputMatchToLog(resultid, newmatch, true);
+
+        if (prevmatch) {
+            prevmatch->mNext = newmatch;
+        }
+        else {
+            mMatchMap.Put(resultid, newmatch);
+        }
+
+        if (removematch) {
+            newmatch->mNext = removematch->mNext;
+            nsTemplateMatch::Destroy(removematch, true);
+        }
+        else {
+            newmatch->mNext = existingmatch;
+        }
+    }
+
+    return rv;
+}
+
+nsresult
+nsXULContentBuilder::EnsureElementHasGenericChild(nsIContent* parent,
+                                                  int32_t nameSpaceID,
+                                                  nsIAtom* tag,
+                                                  bool aNotify,
+                                                  nsIContent** result)
+{
+    nsresult rv;
+
+    rv = nsXULContentUtils::FindChildByTag(parent, nameSpaceID, tag, result);
+    if (NS_FAILED(rv))
+        return rv;
+
+    if (rv == NS_RDF_NO_VALUE) {
+        // we need to construct a new child element.
+        nsCOMPtr<Element> element;
+
+        rv = CreateElement(nameSpaceID, tag, getter_AddRefs(element));
+        if (NS_FAILED(rv))
+            return rv;
+
+        // XXX Note that the notification ensures we won't batch insertions! This could be bad! - Dave
+        rv = parent->AppendChildTo(element, aNotify);
+        if (NS_FAILED(rv))
+            return rv;
+
+        *result = element;
+        NS_ADDREF(*result);
+        return NS_ELEMENT_GOT_CREATED;
+    }
+    else {
+        return NS_ELEMENT_WAS_THERE;
+    }
+}
+
+bool
+nsXULContentBuilder::IsOpen(nsIContent* aElement)
+{
+    // Determine if this is a <treeitem> or <menu> element
+    if (!aElement->IsXUL())
+        return true;
+
+    // XXXhyatt Use the XBL service to obtain a base tag.
+    nsIAtom *tag = aElement->Tag();
+    if (tag == nsGkAtoms::menu ||
+        tag == nsGkAtoms::menubutton ||
+        tag == nsGkAtoms::toolbarbutton ||
+        tag == nsGkAtoms::button ||
+        tag == nsGkAtoms::treeitem)
+        return aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::open,
+                                     nsGkAtoms::_true, eCaseMatters);
+    return true;
+}
+
+nsresult
+nsXULContentBuilder::RemoveGeneratedContent(nsIContent* aElement)
+{
+    // Keep a queue of "ungenerated" elements that we have to probe
+    // for generated content.
+    nsAutoTArray<nsIContent*, 8> ungenerated;
+    if (ungenerated.AppendElement(aElement) == nullptr)
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    uint32_t count;
+    while (0 != (count = ungenerated.Length())) {
+        // Pull the next "ungenerated" element off the queue.
+        uint32_t last = count - 1;
+        nsCOMPtr<nsIContent> element = ungenerated[last];
+        ungenerated.RemoveElementAt(last);
+
+        uint32_t i = element->GetChildCount();
+
+        while (i-- > 0) {
+            nsCOMPtr<nsIContent> child = element->GetChildAt(i);
+
+            // Optimize for the <template> element, because we *know*
+            // it won't have any generated content: there's no reason
+            // to even check this subtree.
+            // XXX should this check |child| rather than |element|? Otherwise
+            //     it should be moved outside the inner loop. Bug 297290.
+            if (element->NodeInfo()->Equals(nsGkAtoms::_template,
+                                            kNameSpaceID_XUL) ||
+                !element->IsElement())
+                continue;
+
+            // If the element is in the template map, then we
+            // assume it's been generated and nuke it.
+            nsCOMPtr<nsIContent> tmpl;
+            mTemplateMap.GetTemplateFor(child, getter_AddRefs(tmpl));
+
+            if (! tmpl) {
+                // No 'template' attribute, so this must not have been
+                // generated. We'll need to examine its kids.
+                if (ungenerated.AppendElement(child) == nullptr)
+                    return NS_ERROR_OUT_OF_MEMORY;
+                continue;
+            }
+
+            // If we get here, it's "generated". Bye bye!
+            element->RemoveChildAt(i, true);
+
+            // Remove this and any children from the content support map.
+            mContentSupportMap.Remove(child);
+
+            // Remove from the template map
+            mTemplateMap.Remove(child);
+        }
+    }
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::GetElementsForResult(nsIXULTemplateResult* aResult,
+                                          nsCOMArray<nsIContent>& aElements)
+{
+    // if the root has been removed from the document, just return
+    // since there won't be any generated content any more
+    nsCOMPtr<nsIXULDocument> xuldoc = do_QueryInterface(mRoot->GetDocument());
+    if (! xuldoc)
+        return NS_OK;
+
+    nsAutoString id;
+    aResult->GetId(id);
+
+    xuldoc->GetElementsForID(id, aElements);
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CreateElement(int32_t aNameSpaceID,
+                                   nsIAtom* aTag,
+                                   Element** aResult)
+{
+    nsCOMPtr<nsIDocument> doc = mRoot->GetDocument();
+    NS_ASSERTION(doc != nullptr, "not initialized");
+    if (! doc)
+        return NS_ERROR_NOT_INITIALIZED;
+
+    nsCOMPtr<nsINodeInfo> nodeInfo =
+        doc->NodeInfoManager()->GetNodeInfo(aTag, nullptr, aNameSpaceID,
+                                            nsIDOMNode::ELEMENT_NODE);
+
+    return NS_NewElement(aResult, nodeInfo.forget(), NOT_FROM_PARSER);
+}
+
+nsresult
+nsXULContentBuilder::SetContainerAttrs(nsIContent *aElement,
+                                       nsIXULTemplateResult* aResult,
+                                       bool aIgnoreNonContainers,
+                                       bool aNotify)
+{
+    NS_PRECONDITION(aResult != nullptr, "null ptr");
+    if (! aResult)
+        return NS_ERROR_NULL_POINTER;
+
+    bool iscontainer;
+    aResult->GetIsContainer(&iscontainer);
+
+    if (aIgnoreNonContainers && !iscontainer)
+        return NS_OK;
+
+    NS_NAMED_LITERAL_STRING(true_, "true");
+    NS_NAMED_LITERAL_STRING(false_, "false");
+
+    const nsAString& newcontainer =
+        iscontainer ? true_ : false_;
+
+    aElement->SetAttr(kNameSpaceID_None, nsGkAtoms::container,
+                      newcontainer, aNotify);
+
+    if (iscontainer && !(mFlags & eDontTestEmpty)) {
+        bool isempty;
+        aResult->GetIsEmpty(&isempty);
+
+        const nsAString& newempty =
+            (iscontainer && isempty) ? true_ : false_;
+
+        aElement->SetAttr(kNameSpaceID_None, nsGkAtoms::empty,
+                          newempty, aNotify);
+    }
+
+    return NS_OK;
+}
+
+
+//----------------------------------------------------------------------
+//
+// nsIXULTemplateBuilder methods
+//
+
+NS_IMETHODIMP
+nsXULContentBuilder::CreateContents(nsIContent* aElement, bool aForceCreation)
+{
+    NS_PRECONDITION(aElement != nullptr, "null ptr");
+    if (! aElement)
+        return NS_ERROR_NULL_POINTER;
+
+    // don't build contents for closed elements. aForceCreation will be true
+    // when a menu is about to be opened, so the content should be built anyway.
+    if (!aForceCreation && !IsOpen(aElement))
+        return NS_OK;
+
+    return CreateTemplateAndContainerContents(aElement, aForceCreation);
+}
+
+NS_IMETHODIMP
+nsXULContentBuilder::HasGeneratedContent(nsIRDFResource* aResource,
+                                         nsIAtom* aTag,
+                                         bool* aGenerated)
+{
+    *aGenerated = false;
+    NS_ENSURE_TRUE(mRoot, NS_ERROR_NOT_INITIALIZED);
+    NS_ENSURE_STATE(mRootResult);
+
+    nsCOMPtr<nsIRDFResource> rootresource;
+    nsresult rv = mRootResult->GetResource(getter_AddRefs(rootresource));
+    if (NS_FAILED(rv))
+        return rv;
+
+    // the root resource is always acceptable
+    if (aResource == rootresource) {
+        if (!aTag || mRoot->Tag() == aTag)
+            *aGenerated = true;
+    }
+    else {
+        const char* uri;
+        aResource->GetValueConst(&uri);
+
+        NS_ConvertUTF8toUTF16 refID(uri);
+
+        // just return if the node is no longer in a document
+        nsCOMPtr<nsIXULDocument> xuldoc = do_QueryInterface(mRoot->GetDocument());
+        if (! xuldoc)
+            return NS_OK;
+
+        nsCOMArray<nsIContent> elements;
+        xuldoc->GetElementsForID(refID, elements);
+
+        uint32_t cnt = elements.Count();
+
+        for (int32_t i = int32_t(cnt) - 1; i >= 0; --i) {
+            nsCOMPtr<nsIContent> content = elements.SafeObjectAt(i);
+
+            do {
+                nsTemplateMatch* match;
+                if (content == mRoot || mContentSupportMap.Get(content, &match)) {
+                    // If we've got a tag, check it to ensure we're consistent.
+                    if (!aTag || content->Tag() == aTag) {
+                        *aGenerated = true;
+                        return NS_OK;
+                    }
+                }
+
+                content = content->GetParent();
+            } while (content);
+        }
+    }
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULContentBuilder::GetResultForContent(nsIDOMElement* aElement,
+                                         nsIXULTemplateResult** aResult)
+{
+    NS_ENSURE_ARG_POINTER(aElement);
+    NS_ENSURE_ARG_POINTER(aResult);
+
+    nsCOMPtr<nsIContent> content = do_QueryInterface(aElement);
+    if (content == mRoot) {
+        *aResult = mRootResult;
+    }
+    else {
+        nsTemplateMatch *match = nullptr;
+        if (mContentSupportMap.Get(content, &match))
+            *aResult = match->mResult;
+        else
+            *aResult = nullptr;
+    }
+
+    NS_IF_ADDREF(*aResult);
+    return NS_OK;
+}
+
+//----------------------------------------------------------------------
+//
+// nsIDocumentObserver methods
+//
+
+void
+nsXULContentBuilder::AttributeChanged(nsIDocument* aDocument,
+                                      Element*     aElement,
+                                      int32_t      aNameSpaceID,
+                                      nsIAtom*     aAttribute,
+                                      int32_t      aModType)
+{
+    nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+
+    // Handle "open" and "close" cases. We do this handling before
+    // we've notified the observer, so that content is already created
+    // for the frame system to walk.
+    if (aElement->GetNameSpaceID() == kNameSpaceID_XUL &&
+        aAttribute == nsGkAtoms::open) {
+        // We're on a XUL tag, and an ``open'' attribute changed.
+        if (aElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::open,
+                                  nsGkAtoms::_true, eCaseMatters))
+            OpenContainer(aElement);
+        else
+            CloseContainer(aElement);
+    }
+
+    if ((aNameSpaceID == kNameSpaceID_XUL) &&
+        ((aAttribute == nsGkAtoms::sort) ||
+         (aAttribute == nsGkAtoms::sortDirection) ||
+         (aAttribute == nsGkAtoms::sortResource) ||
+         (aAttribute == nsGkAtoms::sortResource2)))
+        mSortState.initialized = false;
+
+    // Pass along to the generic template builder.
+    nsXULTemplateBuilder::AttributeChanged(aDocument, aElement, aNameSpaceID,
+                                           aAttribute, aModType);
+}
+
+void
+nsXULContentBuilder::NodeWillBeDestroyed(const nsINode* aNode)
+{
+    nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+    // Break circular references
+    mContentSupportMap.Clear();
+
+    nsXULTemplateBuilder::NodeWillBeDestroyed(aNode);
+}
+
+
+//----------------------------------------------------------------------
+//
+// nsXULTemplateBuilder methods
+//
+
+bool
+nsXULContentBuilder::GetInsertionLocations(nsIXULTemplateResult* aResult,
+                                           nsCOMArray<nsIContent>** aLocations)
+{
+    *aLocations = nullptr;
+
+    nsAutoString ref;
+    nsresult rv = aResult->GetBindingFor(mRefVariable, ref);
+    if (NS_FAILED(rv))
+        return false;
+
+    nsCOMPtr<nsIXULDocument> xuldoc = do_QueryInterface(mRoot->GetDocument());
+    if (! xuldoc)
+        return false;
+
+    *aLocations = new nsCOMArray<nsIContent>;
+    NS_ENSURE_TRUE(*aLocations, false);
+
+    xuldoc->GetElementsForID(ref, **aLocations);
+    uint32_t count = (*aLocations)->Count();
+
+    bool found = false;
+
+    for (uint32_t t = 0; t < count; t++) {
+        nsCOMPtr<nsIContent> content = (*aLocations)->SafeObjectAt(t);
+
+        nsTemplateMatch* refmatch;
+        if (content == mRoot || mContentSupportMap.Get(content, &refmatch)) {
+            // See if we've built the container contents for "content"
+            // yet. If not, we don't need to build any content. This
+            // happens, for example, if we receive an assertion on a
+            // closed folder in a tree widget or on a menu that hasn't
+            // yet been opened.
+            nsXULElement *xulcontent = nsXULElement::FromContent(content);
+            if (!xulcontent || xulcontent->GetTemplateGenerated()) {
+                found = true;
+                continue;
+            }
+        }
+
+        // clear the item in the list since we don't want to insert there
+        (*aLocations)->ReplaceObjectAt(nullptr, t);
+    }
+
+    return found;
+}
+
+nsresult
+nsXULContentBuilder::ReplaceMatch(nsIXULTemplateResult* aOldResult,
+                                  nsTemplateMatch* aNewMatch,
+                                  nsTemplateRule* aNewMatchRule,
+                                  void *aContext)
+
+{
+    nsresult rv;
+    nsIContent* content = static_cast<nsIContent*>(aContext);
+
+    // update the container attributes for the match
+    if (content) {
+        nsAutoString ref;
+        if (aNewMatch)
+            rv = aNewMatch->mResult->GetBindingFor(mRefVariable, ref);
+        else
+            rv = aOldResult->GetBindingFor(mRefVariable, ref);
+        if (NS_FAILED(rv))
+            return rv;
+
+        if (!ref.IsEmpty()) {
+            nsCOMPtr<nsIXULTemplateResult> refResult;
+            rv = GetResultForId(ref, getter_AddRefs(refResult));
+            if (NS_FAILED(rv))
+                return rv;
+
+            if (refResult)
+                SetContainerAttrs(content, refResult, false, true);
+        }
+    }
+
+    if (aOldResult) {
+        nsCOMArray<nsIContent> elements;
+        rv = GetElementsForResult(aOldResult, elements);
+        if (NS_FAILED(rv))
+            return rv;
+
+        uint32_t count = elements.Count();
+
+        for (int32_t e = int32_t(count) - 1; e >= 0; --e) {
+            nsCOMPtr<nsIContent> child = elements.SafeObjectAt(e);
+
+            nsTemplateMatch* match;
+            if (mContentSupportMap.Get(child, &match)) {
+                if (content == match->GetContainer())
+                    RemoveMember(child);
+            }
+        }
+    }
+
+    if (aNewMatch) {
+        nsCOMPtr<nsIContent> action = aNewMatchRule->GetAction();
+        return BuildContentFromTemplate(action, content, content, true,
+                                        mRefVariable == aNewMatchRule->GetMemberVariable(),
+                                        aNewMatch->mResult, true, aNewMatch,
+                                        nullptr, nullptr);
+    }
+
+    return NS_OK;
+}
+
+
+nsresult
+nsXULContentBuilder::SynchronizeResult(nsIXULTemplateResult* aResult)
+{
+    nsCOMArray<nsIContent> elements;
+    GetElementsForResult(aResult, elements);
+
+    uint32_t cnt = elements.Count();
+
+    for (int32_t i = int32_t(cnt) - 1; i >= 0; --i) {
+        nsCOMPtr<nsIContent> element = elements.SafeObjectAt(i);
+
+        nsTemplateMatch* match;
+        if (! mContentSupportMap.Get(element, &match))
+            continue;
+
+        nsCOMPtr<nsIContent> templateNode;
+        mTemplateMap.GetTemplateFor(element, getter_AddRefs(templateNode));
+
+        NS_ASSERTION(templateNode, "couldn't find template node for element");
+        if (! templateNode)
+            continue;
+
+        // this node was created by a XUL template, so update it accordingly
+        SynchronizeUsingTemplate(templateNode, element, aResult);
+    }
+
+    return NS_OK;
+}
+
+//----------------------------------------------------------------------
+//
+// Implementation methods
+//
+
+nsresult
+nsXULContentBuilder::OpenContainer(nsIContent* aElement)
+{
+    if (aElement != mRoot) {
+        if (mFlags & eDontRecurse)
+            return NS_OK;
+
+        bool rightBuilder = false;
+
+        nsCOMPtr<nsIXULDocument> xuldoc = do_QueryInterface(aElement->GetDocument());
+        if (! xuldoc)
+            return NS_OK;
+
+        // See if we're responsible for this element
+        nsIContent* content = aElement;
+        do {
+            nsCOMPtr<nsIXULTemplateBuilder> builder;
+            xuldoc->GetTemplateBuilderFor(content, getter_AddRefs(builder));
+            if (builder) {
+                if (builder == this)
+                    rightBuilder = true;
+                break;
+            }
+
+            content = content->GetParent();
+        } while (content);
+
+        if (! rightBuilder)
+            return NS_OK;
+    }
+
+    CreateTemplateAndContainerContents(aElement, false);
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::CloseContainer(nsIContent* aElement)
+{
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::RebuildAll()
+{
+    NS_ENSURE_TRUE(mRoot, NS_ERROR_NOT_INITIALIZED);
+
+    // Bail out early if we are being torn down.
+    nsCOMPtr<nsIDocument> doc = mRoot->GetDocument();
+    if (!doc)
+        return NS_OK;
+
+    if (mQueriesCompiled)
+        Uninit(false);
+
+    nsresult rv = CompileQueries();
+    if (NS_FAILED(rv))
+        return rv;
+
+    if (mQuerySets.Length() == 0)
+        return NS_OK;
+
+    nsXULElement *xulcontent = nsXULElement::FromContent(mRoot);
+    if (xulcontent)
+        xulcontent->ClearTemplateGenerated();
+
+    // Now, regenerate both the template- and container-generated
+    // contents for the current element...
+    CreateTemplateAndContainerContents(mRoot, false);
+
+    return NS_OK;
+}
+
+/**** Sorting Methods ****/
+
+nsresult
+nsXULContentBuilder::CompareResultToNode(nsIXULTemplateResult* aResult,
+                                         nsIContent* aContent,
+                                         int32_t* aSortOrder)
+{
+    NS_ASSERTION(aSortOrder, "CompareResultToNode: null out param aSortOrder");
+  
+    *aSortOrder = 0;
+
+    nsTemplateMatch *match = nullptr;
+    if (!mContentSupportMap.Get(aContent, &match)) {
+        *aSortOrder = mSortState.sortStaticsLast ? -1 : 1;
+        return NS_OK;
+    }
+
+    if (!mQueryProcessor)
+        return NS_OK;
+
+    if (mSortState.direction == nsSortState_natural) {
+        // sort in natural order
+        nsresult rv = mQueryProcessor->CompareResults(aResult, match->mResult,
+                                                      nullptr, mSortState.sortHints,
+                                                      aSortOrder);
+        NS_ENSURE_SUCCESS(rv, rv);
+    }
+    else {
+        // iterate over each sort key and compare. If the nodes are equal,
+        // continue to compare using the next sort key. If not equal, stop.
+        int32_t length = mSortState.sortKeys.Count();
+        for (int32_t t = 0; t < length; t++) {
+            nsresult rv = mQueryProcessor->CompareResults(aResult, match->mResult,
+                                                          mSortState.sortKeys[t],
+                                                          mSortState.sortHints, aSortOrder);
+            NS_ENSURE_SUCCESS(rv, rv);
+
+            if (*aSortOrder)
+                break;
+        }
+    }
+
+    // flip the sort order if performing a descending sorting
+    if (mSortState.direction == nsSortState_descending)
+        *aSortOrder = -*aSortOrder;
+
+    return NS_OK;
+}
+
+nsresult
+nsXULContentBuilder::InsertSortedNode(nsIContent* aContainer,
+                                      nsIContent* aNode,
+                                      nsIXULTemplateResult* aResult,
+                                      bool aNotify)
+{
+    nsresult rv;
+
+    if (!mSortState.initialized) {
+        nsAutoString sort, sortDirection, sortHints;
+        mRoot->GetAttr(kNameSpaceID_None, nsGkAtoms::sort, sort);
+        mRoot->GetAttr(kNameSpaceID_None, nsGkAtoms::sortDirection, sortDirection);
+        mRoot->GetAttr(kNameSpaceID_None, nsGkAtoms::sorthints, sortHints);
+        sortDirection.AppendLiteral(" ");
+        sortDirection += sortHints;
+        rv = XULSortServiceImpl::InitializeSortState(mRoot, aContainer,
+                                                     sort, sortDirection, &mSortState);
+        NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    // when doing a natural sort, items will typically be sorted according to
+    // the order they appear in the datasource. For RDF, cache whether the
+    // reference parent is an RDF Seq. That way, the items can be sorted in the
+    // order they are in the Seq.
+    mSortState.isContainerRDFSeq = false;
+    if (mSortState.direction == nsSortState_natural) {
+        nsCOMPtr<nsISupports> ref;
+        nsresult rv = aResult->GetBindingObjectFor(mRefVariable, getter_AddRefs(ref));
+        NS_ENSURE_SUCCESS(rv, rv);
+
+        nsCOMPtr<nsIRDFResource> container = do_QueryInterface(ref);
+
+        if (container) {
+            rv = gRDFContainerUtils->IsSeq(mDB, container, &mSortState.isContainerRDFSeq);
+            NS_ENSURE_SUCCESS(rv, rv);
+        }
+    }
+
+    bool childAdded = false;
+    uint32_t numChildren = aContainer->GetChildCount();
+
+    if (mSortState.direction != nsSortState_natural ||
+        (mSortState.direction == nsSortState_natural && mSortState.isContainerRDFSeq))
+    {
+        // because numChildren gets modified
+        int32_t realNumChildren = numChildren;
+        nsIContent *child = nullptr;
+
+        // rjc says: determine where static XUL ends and generated XUL/RDF begins
+        int32_t staticCount = 0;
+
+        nsAutoString staticValue;
+        aContainer->GetAttr(kNameSpaceID_None, nsGkAtoms::staticHint, staticValue);
+        if (!staticValue.IsEmpty())
+        {
+            // found "static" XUL element count hint
+            nsresult strErr = NS_OK;
+            staticCount = staticValue.ToInteger(&strErr);
+            if (NS_FAILED(strErr))
+                staticCount = 0;
+        } else {
+            // compute the "static" XUL element count
+            for (nsIContent* child = aContainer->GetFirstChild();
+                 child;
+                 child = child->GetNextSibling()) {
+                 
+                if (nsContentUtils::HasNonEmptyAttr(child, kNameSpaceID_None,
+                                                    nsGkAtoms::_template))
+                    break;
+                else
+                    ++staticCount;
+            }
+
+            if (mSortState.sortStaticsLast) {
+                // indicate that static XUL comes after RDF-generated content by
+                // making negative
+                staticCount = -staticCount;
+            }
+
+            // save the "static" XUL element count hint
+            nsAutoString valueStr;
+            valueStr.AppendInt(staticCount);
+            aContainer->SetAttr(kNameSpaceID_None, nsGkAtoms::staticHint, valueStr, false);
+        }
+
+        if (staticCount <= 0) {
+            numChildren += staticCount;
+            staticCount = 0;
+        } else if (staticCount > (int32_t)numChildren) {
+            staticCount = numChildren;
+            numChildren -= staticCount;
+        }
+
+        // figure out where to insert the node when a sort order is being imposed
+        if (numChildren > 0) {
+            nsIContent *temp;
+            int32_t direction;
+
+            // rjc says: The following is an implementation of a fairly optimal
+            // binary search insertion sort... with interpolation at either end-point.
+
+            if (mSortState.lastWasFirst) {
+                child = aContainer->GetChildAt(staticCount);
+                temp = child;
+                rv = CompareResultToNode(aResult, temp, &direction);
+                if (direction < 0) {
+                    aContainer->InsertChildAt(aNode, staticCount, aNotify);
+                    childAdded = true;
+                } else
+                    mSortState.lastWasFirst = false;
+            } else if (mSortState.lastWasLast) {
+                child = aContainer->GetChildAt(realNumChildren - 1);
+                temp = child;
+                rv = CompareResultToNode(aResult, temp, &direction);
+                if (direction > 0) {
+                    aContainer->InsertChildAt(aNode, realNumChildren, aNotify);
+                    childAdded = true;
+                } else
+                    mSortState.lastWasLast = false;
+            }
+
+            int32_t left = staticCount + 1, right = realNumChildren, x;
+            while (!childAdded && right >= left) {
+                x = (left + right) / 2;
+                child = aContainer->GetChildAt(x - 1);
+                temp = child;
+
+                rv = CompareResultToNode(aResult, temp, &direction);
+                if ((x == left && direction < 0) ||
+                    (x == right && direction >= 0) ||
+                    left == right)
+                {
+                    int32_t thePos = (direction > 0 ? x : x - 1);
+                    aContainer->InsertChildAt(aNode, thePos, aNotify);
+                    childAdded = true;
+
+                    mSortState.lastWasFirst = (thePos == staticCount);
+                    mSortState.lastWasLast = (thePos >= realNumChildren);
+
+                    break;
+                }
+                if (direction < 0)
+                    right = x - 1;
+                else
+                    left = x + 1;
+            }
+        }
+    }
+
+    // if the child hasn't been inserted yet, just add it at the end. Note
+    // that an append isn't done as there may be static content afterwards.
+    if (!childAdded)
+        aContainer->InsertChildAt(aNode, numChildren, aNotify);
+
+    return NS_OK;
+}