Enable APZ for all Desktop windows if E10s is enabled. (bug 1163115, r=kats)

gfx/layers/ipc/CompositorParent.cpp

@@ -49,6 +49,7 @@
 #include "nsDebug.h"                    // for NS_ASSERTION, etc
 #include "nsISupportsImpl.h"            // for MOZ_COUNT_CTOR, etc
 #include "nsIWidget.h"                  // for nsIWidget
+#include "nsIXULRuntime.h"              // for mozilla::BrowserTabsRemoteAutostart
 #include "nsTArray.h"                   // for nsTArray
 #include "nsThreadUtils.h"              // for NS_IsMainThread
 #include "nsXULAppAPI.h"                // for XRE_GetIOMessageLoop
@@ -664,10 +665,10 @@ CompositorParent::CompositorParent(nsIWidget* aWidget,
   if (gfxPrefs::AsyncPanZoomEnabled() &&
 #if !defined(MOZ_B2G) && !defined(MOZ_WIDGET_ANDROID)
       // For XUL applications (everything but B2G on mobile and desktop, and
-      // Firefox on Android) we only want to use APZ in e10s-enabled windows.
-      // If we ever get input events off the main thread we can consider
-      // relaxing this requirement.
-      aWidget->IsMultiProcessWindow() &&
+      // Firefox on Android) we only want to use APZ when E10S is enabled. If
+      // we ever get input events off the main thread we can consider relaxing
+      // this requirement.
+      mozilla::BrowserTabsRemoteAutostart() &&
 #endif
       (aWidget->WindowType() == eWindowType_toplevel || aWidget->WindowType() == eWindowType_child)) {
     mApzcTreeManager = new APZCTreeManager();

widget/cocoa/nsChildView.h

@@ -487,7 +487,6 @@ public:
 #endif
 
   virtual void CreateCompositor() override;
-  virtual bool IsMultiProcessWindow() override;
   virtual void PrepareWindowEffects() override;
   virtual void CleanupWindowEffects() override;
   virtual bool PreRender(LayerManagerComposite* aManager) override;

widget/cocoa/nsChildView.mm

@@ -1929,16 +1929,6 @@ nsChildView::CreateCompositor()
   }
 }
 
-bool
-nsChildView::IsMultiProcessWindow()
-{
-  // On OS X the XULWindowWidget object gets the widget's init-data, which
-  // is what has the electrolysis window flag. So here in the child view
-  // we need to get the flag from that window instead.
-  nsCocoaWindow* parent = GetXULWindowWidget();
-  return parent ? parent->IsMultiProcessWindow() : false;
-}
-
 void
 nsChildView::ConfigureAPZCTreeManager()
 {

widget/nsBaseWidget.cpp

@@ -295,7 +295,6 @@ void nsBaseWidget::BaseCreate(nsIWidget *aParent,
     mBorderStyle = aInitData->mBorderStyle;
     mPopupLevel = aInitData->mPopupLevel;
     mPopupType = aInitData->mPopupHint;
-    mMultiProcessWindow = aInitData->mMultiProcessWindow;
   }
 
   if (aParent) {
@@ -953,11 +952,6 @@ private:
   nsRefPtr<APZCTreeManager> mTreeManager;
 };
 
-bool nsBaseWidget::IsMultiProcessWindow()
-{
-  return mMultiProcessWindow;
-}
-
 void nsBaseWidget::ConfigureAPZCTreeManager()
 {
   MOZ_ASSERT(mAPZC);

widget/nsBaseWidget.h

@@ -154,7 +154,6 @@ public:
   virtual CompositorParent* NewCompositorParent(int aSurfaceWidth, int aSurfaceHeight);
   virtual void            CreateCompositor();
   virtual void            CreateCompositor(int aWidth, int aHeight);
-  virtual bool            IsMultiProcessWindow() override;
   virtual void            PrepareWindowEffects() override {}
   virtual void            CleanupWindowEffects() override {}
   virtual bool            PreRender(LayerManagerComposite* aManager) override { return true; }
@@ -482,7 +481,6 @@ protected:
   bool              mUpdateCursor;
   nsBorderStyle     mBorderStyle;
   bool              mUseLayersAcceleration;
-  bool              mMultiProcessWindow;
   bool              mUseAttachedEvents;
   nsIntRect         mBounds;
   nsIntRect*        mOriginalBounds;

widget/nsIWidget.h

@@ -1751,8 +1751,6 @@ class nsIWidget : public nsISupports {
     NS_IMETHOD DispatchEvent(mozilla::WidgetGUIEvent* event,
                              nsEventStatus & aStatus) = 0;
 
-    virtual bool IsMultiProcessWindow() = 0;
-
     /**
      * Dispatches an event that must be handled by APZ first, when APZ is
      * enabled. If invoked in the child process, it is forwarded to the

widget/nsWidgetInitData.h

@@ -105,8 +105,7 @@ struct nsWidgetInitData {
       mIsDragPopup(false),
       mIsAnimationSuppressed(false),
       mSupportTranslucency(false),
-      mMouseTransparent(false),
-      mMultiProcessWindow(false)
+      mMouseTransparent(false)
   {
   }
 
@@ -132,8 +131,6 @@ struct nsWidgetInitData {
   // true if the window should be transparent to mouse events. Currently this is
   // only valid for eWindowType_popup widgets
   bool          mMouseTransparent;
-  // This flag designates windows with out-of-process tabs.
-  bool          mMultiProcessWindow;
 };
 
 #endif // nsWidgetInitData_h__

xpfe/appshell/nsAppShellService.cpp

@@ -534,9 +534,6 @@ nsAppShellService::JustCreateTopWindow(nsIXULWindow *aParent,
   if (aChromeMask & nsIWebBrowserChrome::CHROME_MAC_SUPPRESS_ANIMATION)
     widgetInitData.mIsAnimationSuppressed = true;
 
-  if (aChromeMask & nsIWebBrowserChrome::CHROME_REMOTE_WINDOW)
-    widgetInitData.mMultiProcessWindow = true;
-
 #ifdef XP_MACOSX
   // Mac OS X sheet support
   // Adding CHROME_OPENAS_CHROME to sheetMask makes modal windows opened from