diff -r 000000000000 -r 6474c204b198 gfx/thebes/gfxPrefs.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/thebes/gfxPrefs.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,88 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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 "gfxPrefs.h"
+
+#include "mozilla/Preferences.h"
+#include "MainThreadUtils.h"
+
+using namespace mozilla;
+
+gfxPrefs* gfxPrefs::sInstance = nullptr;
+
+void
+gfxPrefs::DestroySingleton()
+{
+  if (sInstance) {
+    delete sInstance;
+    sInstance = nullptr;
+  }
+}
+
+bool
+gfxPrefs::SingletonExists()
+{
+  return sInstance != nullptr;
+}
+
+gfxPrefs::gfxPrefs()
+{
+  // Needs to be created on the main thread.
+  MOZ_ASSERT(NS_IsMainThread(), "must be constructed on the main thread");
+}
+
+gfxPrefs::~gfxPrefs()
+{
+  MOZ_ASSERT(NS_IsMainThread(), "must be destructed on the main thread");
+}
+
+void gfxPrefs::PrefAddVarCache(bool* aVariable,
+                               const char* aPref,
+                               bool aDefault)
+{
+  Preferences::AddBoolVarCache(aVariable, aPref, aDefault);
+}
+
+void gfxPrefs::PrefAddVarCache(int32_t* aVariable,
+                               const char* aPref,
+                               int32_t aDefault)
+{
+  Preferences::AddIntVarCache(aVariable, aPref, aDefault);
+}
+
+void gfxPrefs::PrefAddVarCache(uint32_t* aVariable,
+                               const char* aPref,
+                               uint32_t aDefault)
+{
+  Preferences::AddUintVarCache(aVariable, aPref, aDefault);
+}
+
+void gfxPrefs::PrefAddVarCache(float* aVariable,
+                               const char* aPref,
+                               float aDefault)
+{
+  Preferences::AddFloatVarCache(aVariable, aPref, aDefault);
+}
+
+bool gfxPrefs::PrefGet(const char* aPref, bool aDefault)
+{
+  return Preferences::GetBool(aPref, aDefault);
+}
+
+int32_t gfxPrefs::PrefGet(const char* aPref, int32_t aDefault)
+{
+  return Preferences::GetInt(aPref, aDefault);
+}
+
+uint32_t gfxPrefs::PrefGet(const char* aPref, uint32_t aDefault)
+{
+  return Preferences::GetUint(aPref, aDefault);
+}
+
+float gfxPrefs::PrefGet(const char* aPref, float aDefault)
+{
+  return Preferences::GetFloat(aPref, aDefault);
+}
+