new file mode 100644
--- /dev/null
+++ b/gfx/layers/apz/util/ChromeProcessController.cpp
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; tab-width: 2; 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 "mozilla/layers/ChromeProcessController.h"
+#include "mozilla/layers/CompositorParent.h"
+#include "mozilla/layers/APZCCallbackHelper.h"
+#include "nsLayoutUtils.h"
+
+using namespace mozilla;
+using namespace mozilla::layers;
+using namespace mozilla::widget;
+
+void
+ChromeProcessController::RequestContentRepaint(const FrameMetrics& aFrameMetrics)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(aFrameMetrics.GetScrollId());
+  if (targetContent) {
+    FrameMetrics metrics = aFrameMetrics;
+    APZCCallbackHelper::UpdateSubFrame(targetContent, metrics);
+  }
+}
+
+void
+ChromeProcessController::PostDelayedTask(Task* aTask, int aDelayMs)
+{
+  MessageLoop::current()->PostDelayedTask(FROM_HERE, aTask, aDelayMs);
+}
+
+void
+ChromeProcessController::AcknowledgeScrollUpdate(const FrameMetrics::ViewID& aScrollId,
+                                                 const uint32_t& aScrollGeneration)
+{
+  APZCCallbackHelper::AcknowledgeScrollUpdate(aScrollId, aScrollGeneration);
+}

new file mode 100644
--- /dev/null
+++ b/gfx/layers/apz/util/ChromeProcessController.h
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 2; 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/. */
+
+#ifndef mozilla_layers_ChromeProcessController_h
+#define mozilla_layers_ChromeProcessController_h
+
+#include "mozilla/layers/GeckoContentController.h"
+
+namespace mozilla {
+
+namespace layers {
+class CompositorParent;
+
+// A ChromeProcessController is attached to the root of a compositor's layer
+// tree.
+class ChromeProcessController : public mozilla::layers::GeckoContentController
+{
+  typedef mozilla::layers::FrameMetrics FrameMetrics;
+  typedef mozilla::layers::ScrollableLayerGuid ScrollableLayerGuid;
+
+public:
+  // GeckoContentController interface
+  virtual void RequestContentRepaint(const FrameMetrics& aFrameMetrics) MOZ_OVERRIDE;
+  virtual void PostDelayedTask(Task* aTask, int aDelayMs) MOZ_OVERRIDE;
+  virtual void AcknowledgeScrollUpdate(const FrameMetrics::ViewID& aScrollId,
+                                       const uint32_t& aScrollGeneration) MOZ_OVERRIDE;
+
+  virtual void HandleDoubleTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
+                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
+  virtual void HandleSingleTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
+                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
+  virtual void HandleLongTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
+                               const ScrollableLayerGuid& aGuid,
+                               uint64_t aInputBlockId) MOZ_OVERRIDE {}
+  virtual void HandleLongTapUp(const CSSPoint& aPoint, int32_t aModifiers,
+                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
+  virtual void SendAsyncScrollDOMEvent(bool aIsRoot, const mozilla::CSSRect &aContentRect,
+                                       const mozilla::CSSSize &aScrollableSize) MOZ_OVERRIDE {}
+};
+
+} // namespace layers
+} // namespace mozilla
+
+#endif /* mozilla_layers_ChromeProcessController_h */

--- a/gfx/layers/moz.build
+++ b/gfx/layers/moz.build
@@ -108,16 +108,17 @@ EXPORTS.gfxipc += [
 EXPORTS.mozilla.layers += [
     'apz/public/GeckoContentController.h',
     # exporting things from apz/src is temporary until we extract a
     # proper interface for the code there
     'apz/src/APZCTreeManager.h',
     'apz/testutil/APZTestData.h',
     'apz/util/ActiveElementManager.h',
     'apz/util/APZCCallbackHelper.h',
+    'apz/util/ChromeProcessController.h',
     'AtomicRefCountedWithFinalize.h',
     'AxisPhysicsModel.h',
     'AxisPhysicsMSDModel.h',
     'basic/BasicCompositor.h',
     'basic/MacIOSurfaceTextureHostBasic.h',
     'basic/TextureHostBasic.h',
     'client/CanvasClient.h',
     'client/CompositableClient.h',
@@ -239,16 +240,17 @@ UNIFIED_SOURCES += [
     'apz/src/GestureEventListener.cpp',
     'apz/src/InputBlockState.cpp',
     'apz/src/InputQueue.cpp',
     'apz/src/OverscrollHandoffState.cpp',
     'apz/src/TaskThrottler.cpp',
     'apz/testutil/APZTestData.cpp',
     'apz/util/ActiveElementManager.cpp',
     'apz/util/APZCCallbackHelper.cpp',
+    'apz/util/ChromeProcessController.cpp',
     'AxisPhysicsModel.cpp',
     'AxisPhysicsMSDModel.cpp',
     'basic/BasicCanvasLayer.cpp',
     'basic/BasicColorLayer.cpp',
     'basic/BasicCompositor.cpp',
     'basic/BasicContainerLayer.cpp',
     'basic/BasicImages.cpp',
     'basic/BasicLayerManager.cpp',

--- a/widget/cocoa/nsChildView.h
+++ b/widget/cocoa/nsChildView.h
@@ -544,17 +544,16 @@ protected:
   AllocateChildPopupWidget()
   {
     static NS_DEFINE_IID(kCPopUpCID, NS_POPUP_CID);
     nsCOMPtr<nsIWidget> widget = do_CreateInstance(kCPopUpCID);
     return widget.forget();
   }
 
   void ConfigureAPZCTreeManager() MOZ_OVERRIDE;
-  already_AddRefed<GeckoContentController> CreateRootContentController() MOZ_OVERRIDE;
 
   void DoRemoteComposition(const nsIntRect& aRenderRect);
 
   // Overlay drawing functions for OpenGL drawing
   void DrawWindowOverlay(mozilla::layers::GLManager* aManager, nsIntRect aRect);
   void MaybeDrawResizeIndicator(mozilla::layers::GLManager* aManager, const nsIntRect& aRect);
   void MaybeDrawRoundedCorners(mozilla::layers::GLManager* aManager, const nsIntRect& aRect);
   void MaybeDrawTitlebar(mozilla::layers::GLManager* aManager, const nsIntRect& aRect);

--- a/widget/cocoa/nsChildView.mm
+++ b/widget/cocoa/nsChildView.mm
@@ -79,17 +79,17 @@
 
 #include <dlfcn.h>
 
 #include <ApplicationServices/ApplicationServices.h>
 
 #include "GeckoProfiler.h"
 
 #include "nsIDOMWheelEvent.h"
-#include "mozilla/layers/APZCCallbackHelper.h"
+#include "mozilla/layers/ChromeProcessController.h"
 #include "nsLayoutUtils.h"
 #include "InputData.h"
 #include "VibrancyManager.h"
 
 using namespace mozilla;
 using namespace mozilla::layers;
 using namespace mozilla::gl;
 using namespace mozilla::widget;
@@ -388,58 +388,16 @@ public:
 
 protected:
   nsRefPtr<mozilla::gl::GLContext> mGLContext;
   nsAutoPtr<mozilla::layers::ShaderProgramOGL> mRGBARectProgram;
   gfx::Matrix4x4 mProjMatrix;
   GLuint mQuadVBO;
 };
 
-class APZCTMController : public mozilla::layers::GeckoContentController
-{
-  typedef mozilla::layers::FrameMetrics FrameMetrics;
-  typedef mozilla::layers::ScrollableLayerGuid ScrollableLayerGuid;
-
-public:
-  // GeckoContentController interface
-  virtual void RequestContentRepaint(const FrameMetrics& aFrameMetrics)
-  {
-    MOZ_ASSERT(NS_IsMainThread());
-
-    nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(aFrameMetrics.GetScrollId());
-    if (targetContent) {
-      FrameMetrics metrics = aFrameMetrics;
-      APZCCallbackHelper::UpdateSubFrame(targetContent, metrics);
-    }
-  }
-
-  virtual void PostDelayedTask(Task* aTask, int aDelayMs) MOZ_OVERRIDE
-  {
-    MessageLoop::current()->PostDelayedTask(FROM_HERE, aTask, aDelayMs);
-  }
-
-  virtual void AcknowledgeScrollUpdate(const FrameMetrics::ViewID& aScrollId,
-                                       const uint32_t& aScrollGeneration) MOZ_OVERRIDE
-  {
-    APZCCallbackHelper::AcknowledgeScrollUpdate(aScrollId, aScrollGeneration);
-  }
-
-  virtual void HandleDoubleTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
-                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
-  virtual void HandleSingleTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
-                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
-  virtual void HandleLongTap(const mozilla::CSSPoint& aPoint, int32_t aModifiers,
-                               const ScrollableLayerGuid& aGuid,
-                               uint64_t aInputBlockId) MOZ_OVERRIDE {}
-  virtual void HandleLongTapUp(const CSSPoint& aPoint, int32_t aModifiers,
-                               const ScrollableLayerGuid& aGuid) MOZ_OVERRIDE {}
-  virtual void SendAsyncScrollDOMEvent(bool aIsRoot, const mozilla::CSSRect &aContentRect,
-                                       const mozilla::CSSSize &aScrollableSize) MOZ_OVERRIDE {}
-};
-
 } // unnamed namespace
 
 #pragma mark -
 
 nsChildView::nsChildView() : nsBaseWidget()
 , mView(nullptr)
 , mParentView(nullptr)
 , mParentWidget(nullptr)
@@ -1879,23 +1837,16 @@ void
 nsChildView::CreateCompositor()
 {
   nsBaseWidget::CreateCompositor();
   if (mCompositorChild) {
     [(ChildView *)mView setUsingOMTCompositor:true];
   }
 }
 
-already_AddRefed<GeckoContentController>
-nsChildView::CreateRootContentController()
-{
-  nsRefPtr<APZCTMController> controller = new APZCTMController();
-  return controller.forget();
-}
-
 void
 nsChildView::ConfigureAPZCTreeManager()
 {
   nsBaseWidget::ConfigureAPZCTreeManager();
 
   if (gNumberOfWidgetsNeedingEventThread == 0) {
     [EventThreadRunner start];
   }

--- a/widget/nsBaseWidget.cpp
+++ b/widget/nsBaseWidget.cpp
@@ -39,16 +39,17 @@
 #include "mozilla/unused.h"
 #include "nsContentUtils.h"
 #include "gfxPrefs.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/MouseEvents.h"
 #include "GLConsts.h"
 #include "mozilla/unused.h"
 #include "mozilla/layers/APZCTreeManager.h"
+#include "mozilla/layers/ChromeProcessController.h"
 
 #ifdef ACCESSIBILITY
 #include "nsAccessibilityService.h"
 #endif
 
 #ifdef DEBUG
 #include "nsIObserver.h"
 
@@ -910,17 +911,18 @@ void nsBaseWidget::CreateCompositor()
   nsIntRect rect;
   GetBounds(rect);
   CreateCompositor(rect.width, rect.height);
 }
 
 already_AddRefed<GeckoContentController>
 nsBaseWidget::CreateRootContentController()
 {
-  return nullptr;
+  nsRefPtr<GeckoContentController> controller = new ChromeProcessController();
+  return controller.forget();
 }
 
 void nsBaseWidget::ConfigureAPZCTreeManager()
 {
   uint64_t rootLayerTreeId = mCompositorParent->RootLayerTreeId();
   mAPZC = CompositorParent::GetAPZCTreeManager(rootLayerTreeId);
   MOZ_ASSERT(mAPZC);