diff -r 000000000000 -r 6474c204b198 layout/style/nsLayoutStylesheetCache.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/style/nsLayoutStylesheetCache.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,348 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "nsLayoutStylesheetCache.h"
+
+#include "nsAppDirectoryServiceDefs.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/css/Loader.h"
+#include "nsIFile.h"
+#include "nsNetUtil.h"
+#include "nsIObserverService.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIXULRuntime.h"
+#include "nsCSSStyleSheet.h"
+
+using namespace mozilla;
+
+static bool sNumberControlEnabled;
+
+#define NUMBER_CONTROL_PREF "dom.forms.number"
+
+NS_IMPL_ISUPPORTS(
+  nsLayoutStylesheetCache, nsIObserver, nsIMemoryReporter)
+
+nsresult
+nsLayoutStylesheetCache::Observe(nsISupports* aSubject,
+                            const char* aTopic,
+                            const char16_t* aData)
+{
+  if (!strcmp(aTopic, "profile-before-change")) {
+    mUserContentSheet = nullptr;
+    mUserChromeSheet  = nullptr;
+  }
+  else if (!strcmp(aTopic, "profile-do-change")) {
+    InitFromProfile();
+  }
+  else if (strcmp(aTopic, "chrome-flush-skin-caches") == 0 ||
+           strcmp(aTopic, "chrome-flush-caches") == 0) {
+    mScrollbarsSheet = nullptr;
+    mFormsSheet = nullptr;
+    mNumberControlSheet = nullptr;
+  }
+  else {
+    NS_NOTREACHED("Unexpected observer topic.");
+  }
+  return NS_OK;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::ScrollbarsSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  if (!gStyleCache->mScrollbarsSheet) {
+    nsCOMPtr<nsIURI> sheetURI;
+    NS_NewURI(getter_AddRefs(sheetURI),
+              NS_LITERAL_CSTRING("chrome://global/skin/scrollbars.css"));
+
+    // Scrollbars don't need access to unsafe rules
+    if (sheetURI)
+      LoadSheet(sheetURI, gStyleCache->mScrollbarsSheet, false);
+    NS_ASSERTION(gStyleCache->mScrollbarsSheet, "Could not load scrollbars.css.");
+  }
+
+  return gStyleCache->mScrollbarsSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::FormsSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  if (!gStyleCache->mFormsSheet) {
+    nsCOMPtr<nsIURI> sheetURI;
+      NS_NewURI(getter_AddRefs(sheetURI),
+                NS_LITERAL_CSTRING("resource://gre-resources/forms.css"));
+
+    // forms.css needs access to unsafe rules
+    if (sheetURI)
+      LoadSheet(sheetURI, gStyleCache->mFormsSheet, true);
+
+    NS_ASSERTION(gStyleCache->mFormsSheet, "Could not load forms.css.");
+  }
+
+  return gStyleCache->mFormsSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::NumberControlSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  if (!sNumberControlEnabled) {
+    return nullptr;
+  }
+
+  if (!gStyleCache->mNumberControlSheet) {
+    nsCOMPtr<nsIURI> sheetURI;
+    NS_NewURI(getter_AddRefs(sheetURI),
+              NS_LITERAL_CSTRING("resource://gre-resources/number-control.css"));
+
+    if (sheetURI)
+      LoadSheet(sheetURI, gStyleCache->mNumberControlSheet, false);
+
+    NS_ASSERTION(gStyleCache->mNumberControlSheet, "Could not load number-control.css");
+  }
+
+  return gStyleCache->mNumberControlSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::UserContentSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  return gStyleCache->mUserContentSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::UserChromeSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  return gStyleCache->mUserChromeSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::UASheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  return gStyleCache->mUASheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::QuirkSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  return gStyleCache->mQuirkSheet;
+}
+
+nsCSSStyleSheet*
+nsLayoutStylesheetCache::FullScreenOverrideSheet()
+{
+  EnsureGlobal();
+  if (!gStyleCache)
+    return nullptr;
+
+  return gStyleCache->mFullScreenOverrideSheet;
+}
+
+void
+nsLayoutStylesheetCache::Shutdown()
+{
+  NS_IF_RELEASE(gCSSLoader);
+  NS_IF_RELEASE(gStyleCache);
+}
+
+MOZ_DEFINE_MALLOC_SIZE_OF(LayoutStylesheetCacheMallocSizeOf)
+
+NS_IMETHODIMP
+nsLayoutStylesheetCache::CollectReports(nsIHandleReportCallback* aHandleReport,
+                                        nsISupports* aData)
+{
+  return MOZ_COLLECT_REPORT(
+    "explicit/layout/style-sheet-cache", KIND_HEAP, UNITS_BYTES,
+    SizeOfIncludingThis(LayoutStylesheetCacheMallocSizeOf),
+    "Memory used for some built-in style sheets.");
+}
+
+
+size_t
+nsLayoutStylesheetCache::SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
+{
+  size_t n = aMallocSizeOf(this);
+
+  #define MEASURE(s) n += s ? s->SizeOfIncludingThis(aMallocSizeOf) : 0;
+
+  MEASURE(mScrollbarsSheet);
+  MEASURE(mFormsSheet);
+  MEASURE(mNumberControlSheet);
+  MEASURE(mUserContentSheet);
+  MEASURE(mUserChromeSheet);
+  MEASURE(mUASheet);
+  MEASURE(mQuirkSheet);
+  MEASURE(mFullScreenOverrideSheet);
+
+  // Measurement of the following members may be added later if DMD finds it is
+  // worthwhile:
+  // - gCSSLoader
+
+  return n;
+}
+
+nsLayoutStylesheetCache::nsLayoutStylesheetCache()
+{
+  nsCOMPtr<nsIObserverService> obsSvc =
+    mozilla::services::GetObserverService();
+  NS_ASSERTION(obsSvc, "No global observer service?");
+
+  if (obsSvc) {
+    obsSvc->AddObserver(this, "profile-before-change", false);
+    obsSvc->AddObserver(this, "profile-do-change", false);
+    obsSvc->AddObserver(this, "chrome-flush-skin-caches", false);
+    obsSvc->AddObserver(this, "chrome-flush-caches", false);
+  }
+
+  InitFromProfile();
+
+  // And make sure that we load our UA sheets.  No need to do this
+  // per-profile, since they're profile-invariant.
+  nsCOMPtr<nsIURI> uri;
+  NS_NewURI(getter_AddRefs(uri), "resource://gre-resources/ua.css");
+  if (uri) {
+    LoadSheet(uri, mUASheet, true);
+  }
+  NS_ASSERTION(mUASheet, "Could not load ua.css");
+
+  NS_NewURI(getter_AddRefs(uri), "resource://gre-resources/quirk.css");
+  if (uri) {
+    LoadSheet(uri, mQuirkSheet, true);
+  }
+  NS_ASSERTION(mQuirkSheet, "Could not load quirk.css");
+
+  NS_NewURI(getter_AddRefs(uri), "resource://gre-resources/full-screen-override.css");
+  if (uri) {
+    LoadSheet(uri, mFullScreenOverrideSheet, true);
+  }
+  NS_ASSERTION(mFullScreenOverrideSheet, "Could not load full-screen-override.css");
+}
+
+nsLayoutStylesheetCache::~nsLayoutStylesheetCache()
+{
+  mozilla::UnregisterWeakMemoryReporter(this);
+  gStyleCache = nullptr;
+}
+
+void
+nsLayoutStylesheetCache::InitMemoryReporter()
+{
+  mozilla::RegisterWeakMemoryReporter(this);
+}
+
+void
+nsLayoutStylesheetCache::EnsureGlobal()
+{
+  if (gStyleCache) return;
+
+  gStyleCache = new nsLayoutStylesheetCache();
+  if (!gStyleCache) return;
+
+  NS_ADDREF(gStyleCache);
+
+  gStyleCache->InitMemoryReporter();
+
+  Preferences::AddBoolVarCache(&sNumberControlEnabled, NUMBER_CONTROL_PREF,
+                               true);
+}
+
+void
+nsLayoutStylesheetCache::InitFromProfile()
+{
+  nsCOMPtr<nsIXULRuntime> appInfo = do_GetService("@mozilla.org/xre/app-info;1");
+  if (appInfo) {
+    bool inSafeMode = false;
+    appInfo->GetInSafeMode(&inSafeMode);
+    if (inSafeMode)
+      return;
+  }
+  nsCOMPtr<nsIFile> contentFile;
+  nsCOMPtr<nsIFile> chromeFile;
+
+  NS_GetSpecialDirectory(NS_APP_USER_CHROME_DIR,
+                         getter_AddRefs(contentFile));
+  if (!contentFile) {
+    // if we don't have a profile yet, that's OK!
+    return;
+  }
+
+  contentFile->Clone(getter_AddRefs(chromeFile));
+  if (!chromeFile) return;
+
+  contentFile->Append(NS_LITERAL_STRING("userContent.css"));
+  chromeFile->Append(NS_LITERAL_STRING("userChrome.css"));
+
+  LoadSheetFile(contentFile, mUserContentSheet);
+  LoadSheetFile(chromeFile, mUserChromeSheet);
+}
+
+void
+nsLayoutStylesheetCache::LoadSheetFile(nsIFile* aFile, nsRefPtr<nsCSSStyleSheet> &aSheet)
+{
+  bool exists = false;
+  aFile->Exists(&exists);
+
+  if (!exists) return;
+
+  nsCOMPtr<nsIURI> uri;
+  NS_NewFileURI(getter_AddRefs(uri), aFile);
+
+  LoadSheet(uri, aSheet, false);
+}
+
+void
+nsLayoutStylesheetCache::LoadSheet(nsIURI* aURI,
+                                   nsRefPtr<nsCSSStyleSheet> &aSheet,
+                                   bool aEnableUnsafeRules)
+{
+  if (!aURI) {
+    NS_ERROR("Null URI. Out of memory?");
+    return;
+  }
+
+  if (!gCSSLoader) {
+    gCSSLoader = new mozilla::css::Loader();
+    NS_IF_ADDREF(gCSSLoader);
+  }
+
+  if (gCSSLoader) {
+    gCSSLoader->LoadSheetSync(aURI, aEnableUnsafeRules, true,
+                              getter_AddRefs(aSheet));
+  }
+}
+
+nsLayoutStylesheetCache*
+nsLayoutStylesheetCache::gStyleCache = nullptr;
+
+mozilla::css::Loader*
+nsLayoutStylesheetCache::gCSSLoader = nullptr;