diff -r 000000000000 -r 6474c204b198 dom/browser-element/BrowserElementParent.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/browser-element/BrowserElementParent.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,141 @@
+/* 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/. */
+
+#ifndef mozilla_BrowserElementHelpers_h
+#define mozilla_BrowserElementHelpers_h
+
+#include "nsAString.h"
+#include "mozilla/gfx/Point.h"
+#include "mozilla/gfx/Rect.h"
+#include "Units.h"
+#include "mozilla/dom/Element.h"
+
+class nsIDOMWindow;
+class nsIURI;
+
+namespace mozilla {
+
+namespace dom {
+class TabParent;
+}
+
+/**
+ * BrowserElementParent implements a portion of the parent-process side of
+ * <iframe mozbrowser>.
+ *
+ * Most of the parent-process side of <iframe mozbrowser> is implemented in
+ * BrowserElementParent.js.  This file implements the few parts of this
+ * functionality which must be written in C++.
+ *
+ * We don't communicate with the JS code that lives in BrowserElementParent.js;
+ * the JS and C++ parts are completely separate.
+ */
+class BrowserElementParent
+{
+public:
+
+  /**
+   * Possible results from a window.open call.
+   * ADDED     - The frame was added to a document (i.e. handled by the embedder).
+   * IGNORED   - The frame was not added to a document and the embedder didn't
+   *             call preventDefault() to prevent the platform from handling the call.
+   * CANCELLED - The frame was not added to a document, but the embedder still
+   *             called preventDefault() to prevent the platform from handling the call.
+   */
+
+  enum OpenWindowResult {
+    OPEN_WINDOW_ADDED,
+    OPEN_WINDOW_IGNORED,
+    OPEN_WINDOW_CANCELLED
+  };
+
+  /**
+   * Handle a window.open call from an out-of-process <iframe mozbrowser>.
+   *
+   * window.open inside <iframe mozbrowser> doesn't actually open a new
+   * top-level window.  Instead, the "embedder" (the document which contains
+   * the <iframe mozbrowser> whose content called window.open) gets the
+   * opportunity to place a new <iframe mozbrowser> in the DOM somewhere.  This
+   * new "popup" iframe acts as the opened window.
+   *
+   * This method proceeds in three steps.
+   *
+   * 1) We fire a mozbrowseropenwindow CustomEvent on the opener
+   *    iframe element.  This event's detail is an instance of
+   *    OpenWindowEventDetail.
+   *
+   * 2) The embedder (the document which contains the opener iframe) can accept
+   *    the window.open request by inserting event.detail.frameElement (an iframe
+   *    element) into the DOM somewhere.
+   *
+   * 3) If the embedder accepted the window.open request, we return true and
+   *    set aPopupTabParent's frame element to event.detail.frameElement.
+   *    Otherwise, we return false.
+   *
+   * @param aURL the URL the new window should load.  The empty string is
+   *             allowed.
+   * @param aOpenerTabParent the TabParent whose TabChild called window.open.
+   * @param aPopupTabParent the TabParent inside which the opened window will
+   *                        live.
+   * @return an OpenWindowresult that describes whether the embedder added the
+   *         frame to a document and whether it called preventDefault to prevent
+   *         the platform from handling the open request.
+   */
+  static OpenWindowResult
+  OpenWindowOOP(dom::TabParent* aOpenerTabParent,
+                dom::TabParent* aPopupTabParent,
+                const nsAString& aURL,
+                const nsAString& aName,
+                const nsAString& aFeatures);
+
+  /**
+   * Handle a window.open call from an in-process <iframe mozbrowser>.
+   *
+   * (These parameter types are silly, but they match what our caller has in
+   * hand.  Feel free to add an override, if they are inconvenient to you.)
+   *
+   * @param aURI the URI the new window should load.  May be null.
+   * @return an OpenWindowResult that describes whether the browser added the
+   *         frame to a document or whether they called preventDefault to prevent
+   *         the platform from handling the open request
+   */
+  static OpenWindowResult
+  OpenWindowInProcess(nsIDOMWindow* aOpenerWindow,
+                      nsIURI* aURI,
+                      const nsAString& aName,
+                      const nsACString& aFeatures,
+                      nsIDOMWindow** aReturnWindow);
+
+  /**
+   * Fire a mozbrowserasyncscroll CustomEvent on the given TabParent's frame element.
+   * This event's detail is an AsyncScrollEventDetail dictionary.
+   *
+   * @param aContentRect: The portion of the page which is currently visible
+   *                      onscreen in CSS pixels.
+   *
+   * @param aContentSize: The content width/height in CSS pixels.
+   *
+   * aContentRect.top + aContentRect.height may be larger than aContentSize.height.
+   * This indicates that the content is over-scrolled, which occurs when the
+   * page "rubber-bands" after being scrolled all the way to the bottom.
+   * Similarly, aContentRect.left + aContentRect.width may be greater than
+   * contentSize.width, and both left and top may be negative.
+   */
+  static bool
+  DispatchAsyncScrollEvent(dom::TabParent* aTabParent,
+                           const CSSRect& aContentRect,
+                           const CSSSize& aContentSize);
+
+private:
+  static OpenWindowResult
+  DispatchOpenWindowEvent(dom::Element* aOpenerFrameElement,
+                          dom::Element* aPopupFrameElement,
+                          const nsAString& aURL,
+                          const nsAString& aName,
+                          const nsAString& aFeatures);
+};
+
+} // namespace mozilla
+
+#endif