From 881c04e39072a339ade66e7f88ca7d8d642bfc87 Mon Sep 17 00:00:00 2001
From: Steven Michaud <smichaud@pobox.com>
Date: Tue, 16 Oct 2012 20:41:21 +0100
Subject: [PATCH] bug 794038 pt 3 - plugins support for resolution change.
 r=bgirard

---
 dom/plugins/base/PluginPRLibrary.cpp       |  7 ++++++
 dom/plugins/base/PluginPRLibrary.h         |  1 +
 dom/plugins/base/nsNPAPIPluginInstance.cpp | 20 +++++++++++++++++
 dom/plugins/base/nsNPAPIPluginInstance.h   |  1 +
 dom/plugins/base/nsPluginInstanceOwner.cpp |  8 +++++++
 dom/plugins/base/nsPluginInstanceOwner.h   |  1 +
 dom/plugins/ipc/PPluginInstance.ipdl       |  3 +++
 dom/plugins/ipc/PluginInstanceChild.cpp    | 22 ++++++++++++++++++-
 dom/plugins/ipc/PluginInstanceChild.h      |  3 +++
 dom/plugins/ipc/PluginInstanceParent.cpp   |  9 +++++++-
 dom/plugins/ipc/PluginInstanceParent.h     |  1 +
 dom/plugins/ipc/PluginLibrary.h            |  1 +
 dom/plugins/ipc/PluginModuleParent.cpp     | 12 ++++++++++-
 dom/plugins/ipc/PluginModuleParent.h       |  1 +
 dom/plugins/ipc/PluginUtilsOSX.h           |  2 ++
 dom/plugins/ipc/PluginUtilsOSX.mm          | 16 ++++++++++++++
 gfx/2d/QuartzSupport.mm                    | 25 +++++++++++++++++++++-
 layout/generic/nsObjectFrame.cpp           |  9 ++++++++
 view/src/nsViewManager.cpp                 |  3 ++-
 widget/cocoa/nsChildView.mm                | 15 ++++++++-----
 widget/nsGUIEvent.h                        |  8 ++++++-
 21 files changed, 157 insertions(+), 11 deletions(-)

diff --git a/dom/plugins/base/PluginPRLibrary.cpp b/dom/plugins/base/PluginPRLibrary.cpp
index c86566d6eef0..05bc33a8a6ff 100644
--- a/dom/plugins/base/PluginPRLibrary.cpp
+++ b/dom/plugins/base/PluginPRLibrary.cpp
@@ -277,6 +277,13 @@ PluginPRLibrary::IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing)
   *aDrawing = false; 
   return NS_OK;
 }
+nsresult
+PluginPRLibrary::ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor)
+{
+  nsNPAPIPluginInstance* inst = (nsNPAPIPluginInstance*)instance->ndata;
+  NS_ENSURE_TRUE(inst, NS_ERROR_NULL_POINTER);
+  return NS_OK;
+}
 #endif
 
 nsresult
diff --git a/dom/plugins/base/PluginPRLibrary.h b/dom/plugins/base/PluginPRLibrary.h
index f9b25b97bf36..7ba24719cb44 100644
--- a/dom/plugins/base/PluginPRLibrary.h
+++ b/dom/plugins/base/PluginPRLibrary.h
@@ -114,6 +114,7 @@ public:
     virtual bool IsOOP() MOZ_OVERRIDE { return false; }
 #if defined(XP_MACOSX)
     virtual nsresult IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing);
+    virtual nsresult ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor);
 #endif
     virtual nsresult SetBackgroundUnknown(NPP instance) MOZ_OVERRIDE;
     virtual nsresult BeginUpdateBackground(NPP instance,
diff --git a/dom/plugins/base/nsNPAPIPluginInstance.cpp b/dom/plugins/base/nsNPAPIPluginInstance.cpp
index 5fb754c0fed7..444c415f4595 100644
--- a/dom/plugins/base/nsNPAPIPluginInstance.cpp
+++ b/dom/plugins/base/nsNPAPIPluginInstance.cpp
@@ -1081,6 +1081,26 @@ nsresult nsNPAPIPluginInstance::IsRemoteDrawingCoreAnimation(bool* aDrawing)
 #endif
 }
 
+nsresult nsNPAPIPluginInstance::ContentsScaleFactorChanged(double aContentsScaleFactor)
+{
+#ifdef XP_MACOSX
+  if (!mPlugin)
+      return NS_ERROR_FAILURE;
+
+  PluginLibrary* library = mPlugin->GetLibrary();
+  if (!library)
+      return NS_ERROR_FAILURE;
+
+  // We only need to call this if the plugin is running OOP.
+  if (!library->IsOOP())
+      return NS_OK;
+  
+  return library->ContentsScaleFactorChanged(&mNPP, aContentsScaleFactor);
+#else
+  return NS_ERROR_FAILURE;
+#endif
+}
+
 nsresult
 nsNPAPIPluginInstance::GetJSObject(JSContext *cx, JSObject** outObject)
 {
diff --git a/dom/plugins/base/nsNPAPIPluginInstance.h b/dom/plugins/base/nsNPAPIPluginInstance.h
index 31d66d1168a5..b94217accfe4 100644
--- a/dom/plugins/base/nsNPAPIPluginInstance.h
+++ b/dom/plugins/base/nsNPAPIPluginInstance.h
@@ -78,6 +78,7 @@ public:
   nsresult GetValueFromPlugin(NPPVariable variable, void* value);
   nsresult GetDrawingModel(int32_t* aModel);
   nsresult IsRemoteDrawingCoreAnimation(bool* aDrawing);
+  nsresult ContentsScaleFactorChanged(double aContentsScaleFactor);
   nsresult GetJSObject(JSContext *cx, JSObject** outObject);
   bool ShouldCache();
   nsresult IsWindowless(bool* isWindowless);
diff --git a/dom/plugins/base/nsPluginInstanceOwner.cpp b/dom/plugins/base/nsPluginInstanceOwner.cpp
index 3f5688320000..a47d002ea4f9 100644
--- a/dom/plugins/base/nsPluginInstanceOwner.cpp
+++ b/dom/plugins/base/nsPluginInstanceOwner.cpp
@@ -1370,6 +1370,14 @@ bool nsPluginInstanceOwner::IsRemoteDrawingCoreAnimation()
   return coreAnimation;
 }
 
+nsresult nsPluginInstanceOwner::ContentsScaleFactorChanged(double aContentsScaleFactor)
+{
+  if (!mInstance) {
+    return NS_ERROR_NULL_POINTER;
+  }
+  return mInstance->ContentsScaleFactorChanged(aContentsScaleFactor);
+}
+
 NPEventModel nsPluginInstanceOwner::GetEventModel()
 {
   return mEventModel;
diff --git a/dom/plugins/base/nsPluginInstanceOwner.h b/dom/plugins/base/nsPluginInstanceOwner.h
index dedb8da5ab62..e4fcf4cb92d1 100644
--- a/dom/plugins/base/nsPluginInstanceOwner.h
+++ b/dom/plugins/base/nsPluginInstanceOwner.h
@@ -116,6 +116,7 @@ public:
   
   NPDrawingModel GetDrawingModel();
   bool IsRemoteDrawingCoreAnimation();
+  nsresult ContentsScaleFactorChanged(double aContentsScaleFactor);
   NPEventModel GetEventModel();
   static void CARefresh(nsITimer *aTimer, void *aClosure);
   void AddToCARefreshTimer();
diff --git a/dom/plugins/ipc/PPluginInstance.ipdl b/dom/plugins/ipc/PPluginInstance.ipdl
index e50704bebef5..4013c1bafc1a 100644
--- a/dom/plugins/ipc/PPluginInstance.ipdl
+++ b/dom/plugins/ipc/PPluginInstance.ipdl
@@ -118,6 +118,9 @@ child:
     returns (int16_t handled);
   // this is only used on windows to forward WM_WINDOWPOSCHANGE
   async WindowPosChanged(NPRemoteEvent event);
+  // used on OS X to tell the child the contents scale factor
+  // of its parent has changed
+  async ContentsScaleFactorChanged(double aContentsScaleFactor);
 
   // ********************** Async plugins rendering
   // see https://wiki.mozilla.org/Gecko:AsyncPluginPainting
diff --git a/dom/plugins/ipc/PluginInstanceChild.cpp b/dom/plugins/ipc/PluginInstanceChild.cpp
index 8028a3465892..a53e5f798aa4 100644
--- a/dom/plugins/ipc/PluginInstanceChild.cpp
+++ b/dom/plugins/ipc/PluginInstanceChild.cpp
@@ -1013,6 +1013,24 @@ PluginInstanceChild::RecvWindowPosChanged(const NPRemoteEvent& event)
 #endif
 }
 
+bool
+PluginInstanceChild::RecvContentsScaleFactorChanged(const double& aContentsScaleFactor)
+{
+#ifdef XP_MACOSX
+    mContentsScaleFactor = aContentsScaleFactor;
+    if (mShContext) {
+        // Release the shared context so that it is reallocated
+        // with the new size. 
+        ::CGContextRelease(mShContext);
+        mShContext = nullptr;
+    }
+    return true;
+#else
+    NS_RUNTIMEABORT("ContentsScaleFactorChanged is an OSX-only message");
+    return false;
+#endif
+}
+
 #if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
 // Create a new window from NPWindow
 bool PluginInstanceChild::CreateWindow(const NPRemoteWindow& aWindow)
@@ -3957,7 +3975,9 @@ PluginInstanceChild::SwapSurfaces()
         (mDoubleBufferCARenderer.GetFrontSurfaceWidth() != 
             mDoubleBufferCARenderer.GetBackSurfaceWidth() ||
         mDoubleBufferCARenderer.GetFrontSurfaceHeight() != 
-            mDoubleBufferCARenderer.GetBackSurfaceHeight())) {
+            mDoubleBufferCARenderer.GetBackSurfaceHeight() ||
+        mDoubleBufferCARenderer.GetFrontSurfaceContentsScaleFactor() != 
+            mDoubleBufferCARenderer.GetBackSurfaceContentsScaleFactor())) {
 
         mDoubleBufferCARenderer.ClearFrontSurface();
     }
diff --git a/dom/plugins/ipc/PluginInstanceChild.h b/dom/plugins/ipc/PluginInstanceChild.h
index 108f8e6cfb1c..8c2a2dd4e08e 100644
--- a/dom/plugins/ipc/PluginInstanceChild.h
+++ b/dom/plugins/ipc/PluginInstanceChild.h
@@ -126,6 +126,9 @@ protected:
     virtual bool
     RecvWindowPosChanged(const NPRemoteEvent& event) MOZ_OVERRIDE;
 
+    virtual bool
+    RecvContentsScaleFactorChanged(const double& aContentsScaleFactor) MOZ_OVERRIDE;
+
     virtual bool
     AnswerNPP_Destroy(NPError* result);
 
diff --git a/dom/plugins/ipc/PluginInstanceParent.cpp b/dom/plugins/ipc/PluginInstanceParent.cpp
index 234273019dd8..caa8b8a126ed 100644
--- a/dom/plugins/ipc/PluginInstanceParent.cpp
+++ b/dom/plugins/ipc/PluginInstanceParent.cpp
@@ -799,7 +799,14 @@ PluginInstanceParent::IsRemoteDrawingCoreAnimation(bool *aDrawing)
                  NPDrawingModelInvalidatingCoreAnimation == (NPDrawingModel)mDrawingModel);
     return NS_OK;
 }
-#endif
+
+nsresult
+PluginInstanceParent::ContentsScaleFactorChanged(double aContentsScaleFactor)
+{
+    bool rv = SendContentsScaleFactorChanged(aContentsScaleFactor);
+    return rv ? NS_OK : NS_ERROR_FAILURE;
+}
+#endif // #ifdef XP_MACOSX
 
 nsresult
 PluginInstanceParent::SetBackgroundUnknown()
diff --git a/dom/plugins/ipc/PluginInstanceParent.h b/dom/plugins/ipc/PluginInstanceParent.h
index 493b22268af6..571068f3bb1f 100644
--- a/dom/plugins/ipc/PluginInstanceParent.h
+++ b/dom/plugins/ipc/PluginInstanceParent.h
@@ -271,6 +271,7 @@ public:
     nsresult GetImageSize(nsIntSize* aSize);
 #ifdef XP_MACOSX
     nsresult IsRemoteDrawingCoreAnimation(bool *aDrawing);
+    nsresult ContentsScaleFactorChanged(double aContentsScaleFactor);
 #endif
     nsresult SetBackgroundUnknown();
     nsresult BeginUpdateBackground(const nsIntRect& aRect,
diff --git a/dom/plugins/ipc/PluginLibrary.h b/dom/plugins/ipc/PluginLibrary.h
index 1097be308953..1258431ea5d1 100644
--- a/dom/plugins/ipc/PluginLibrary.h
+++ b/dom/plugins/ipc/PluginLibrary.h
@@ -73,6 +73,7 @@ public:
   virtual bool IsOOP() = 0;
 #if defined(XP_MACOSX)
   virtual nsresult IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing) = 0;
+  virtual nsresult ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor) = 0;
 #endif
 
   /**
diff --git a/dom/plugins/ipc/PluginModuleParent.cpp b/dom/plugins/ipc/PluginModuleParent.cpp
index 8a95eb0e9069..24f0244914b7 100755
--- a/dom/plugins/ipc/PluginModuleParent.cpp
+++ b/dom/plugins/ipc/PluginModuleParent.cpp
@@ -1185,7 +1185,17 @@ PluginModuleParent::IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing)
 
     return i->IsRemoteDrawingCoreAnimation(aDrawing);
 }
-#endif
+
+nsresult
+PluginModuleParent::ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor)
+{
+    PluginInstanceParent* i = InstCast(instance);
+    if (!i)
+        return NS_ERROR_FAILURE;
+
+    return i->ContentsScaleFactorChanged(aContentsScaleFactor);
+}
+#endif // #if defined(XP_MACOSX)
 
 bool
 PluginModuleParent::AnswerNPN_GetValue_WithBoolReturn(const NPNVariable& aVariable,
diff --git a/dom/plugins/ipc/PluginModuleParent.h b/dom/plugins/ipc/PluginModuleParent.h
index de419ebeb723..2005929d7bbc 100644
--- a/dom/plugins/ipc/PluginModuleParent.h
+++ b/dom/plugins/ipc/PluginModuleParent.h
@@ -271,6 +271,7 @@ private:
 
 #if defined(XP_MACOSX)
     virtual nsresult IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing);
+    virtual nsresult ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor);
 #endif
 #if defined(MOZ_WIDGET_QT) && (MOZ_PLATFORM_MAEMO == 6)
     virtual nsresult HandleGUIEvent(NPP instance, const nsGUIEvent& anEvent,
diff --git a/dom/plugins/ipc/PluginUtilsOSX.h b/dom/plugins/ipc/PluginUtilsOSX.h
index be88f7bd4442..174ba2e63f37 100644
--- a/dom/plugins/ipc/PluginUtilsOSX.h
+++ b/dom/plugins/ipc/PluginUtilsOSX.h
@@ -50,12 +50,14 @@ public:
   // Returns height in "display pixels".  Multiply by
   // mContentsScaleFactor to get device pixels.
   size_t GetFrontSurfaceHeight();
+  double GetFrontSurfaceContentsScaleFactor();
   // Returns width in "display pixels".  Multiply by
   // mContentsScaleFactor to get device pixels.
   size_t GetBackSurfaceWidth();
   // Returns height in "display pixels".  Multiply by
   // mContentsScaleFactor to get device pixels.
   size_t GetBackSurfaceHeight();
+  double GetBackSurfaceContentsScaleFactor();
   IOSurfaceID GetFrontSurfaceID();
 
   bool HasBackSurface();
diff --git a/dom/plugins/ipc/PluginUtilsOSX.mm b/dom/plugins/ipc/PluginUtilsOSX.mm
index e33ecc5c82fd..44c5df51e4ef 100644
--- a/dom/plugins/ipc/PluginUtilsOSX.mm
+++ b/dom/plugins/ipc/PluginUtilsOSX.mm
@@ -269,6 +269,14 @@ size_t nsDoubleBufferCARenderer::GetFrontSurfaceHeight() {
   return mFrontSurface->GetHeight();
 }
 
+double nsDoubleBufferCARenderer::GetFrontSurfaceContentsScaleFactor() {
+  if (!HasFrontSurface()) {
+    return 1.0;
+  }
+
+  return mFrontSurface->GetContentsScaleFactor();
+}
+
 size_t nsDoubleBufferCARenderer::GetBackSurfaceWidth() {
   if (!HasBackSurface()) {
     return 0;
@@ -285,6 +293,14 @@ size_t nsDoubleBufferCARenderer::GetBackSurfaceHeight() {
   return mBackSurface->GetHeight();
 }
 
+double nsDoubleBufferCARenderer::GetBackSurfaceContentsScaleFactor() {
+  if (!HasBackSurface()) {
+    return 1.0;
+  }
+
+  return mBackSurface->GetContentsScaleFactor();
+}
+
 IOSurfaceID nsDoubleBufferCARenderer::GetFrontSurfaceID() {
   if (!HasFrontSurface()) {
     return 0;
diff --git a/gfx/2d/QuartzSupport.mm b/gfx/2d/QuartzSupport.mm
index cc4319a428ae..f6ef9c1fb7e4 100644
--- a/gfx/2d/QuartzSupport.mm
+++ b/gfx/2d/QuartzSupport.mm
@@ -743,6 +743,21 @@ void nsCARenderer::SetBounds(int aWidth, int aHeight) {
         layer.contentsScale = mContentsScaleFactor;
       }
     }
+  } else {
+    // These settings are the default values.  But they might have been
+    // changed as above if we were previously running in a HiDPI mode
+    // (i.e. if we just switched from that to a non-HiDPI mode).
+    [layer setAffineTransform:CGAffineTransformIdentity];
+    if ([layer respondsToSelector:@selector(setContentsScale:)]) {
+#if !defined(MAC_OS_X_VERSION_10_7) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
+      Class CGBridgeLayerClass = ::NSClassFromString(@"CGBridgeLayer");
+      if (!CGBridgeLayerClass || ![layer isKindOfClass:CGBridgeLayerClass])
+#endif
+      {
+        layer.contentsScale = 1.0;
+      }
+    }
   }
   [CATransaction commit];
 
@@ -838,11 +853,19 @@ nsresult nsCARenderer::Render(int aWidth, int aHeight,
   int renderer_width = caRenderer.bounds.size.width / intScaleFactor;
   int renderer_height = caRenderer.bounds.size.height / intScaleFactor;
 
-  if (renderer_width != aWidth || renderer_height != aHeight) {
+  if (renderer_width != aWidth || renderer_height != aHeight ||
+      mContentsScaleFactor != aContentsScaleFactor) {
     // XXX: This should be optimized to not rescale the buffer
     //      if we are resizing down.
+    // caLayer is the CALayer* provided by the plugin, so we need to preserve
+    // it across the call to Destroy().
     CALayer* caLayer = [caRenderer layer];
+    // mIOSurface is set by AttachIOSurface(), not by SetupRenderer().  So
+    // since it may have been set by a prior call to AttachIOSurface(), we
+    // need to preserve it across the call to Destroy().
+    mozilla::RefPtr<MacIOSurface> ioSurface = mIOSurface;
     Destroy();
+    mIOSurface = ioSurface;
     if (SetupRenderer(caLayer, aWidth, aHeight, aContentsScaleFactor,
                       mAllowOfflineRenderer) != NS_OK) {
       return NS_ERROR_FAILURE;
diff --git a/layout/generic/nsObjectFrame.cpp b/layout/generic/nsObjectFrame.cpp
index 7126627b6998..b5417d2a6afe 100644
--- a/layout/generic/nsObjectFrame.cpp
+++ b/layout/generic/nsObjectFrame.cpp
@@ -2072,6 +2072,15 @@ nsObjectFrame::HandleEvent(nsPresContext* aPresContext,
       return fm->FocusPlugin(GetContent());
   }
 
+#ifdef XP_MACOSX
+  if (anEvent->message == NS_PLUGIN_RESOLUTION_CHANGED) {
+    double scaleFactor = 1.0;
+    mInstanceOwner->GetContentsScaleFactor(&scaleFactor);
+    mInstanceOwner->ContentsScaleFactorChanged(scaleFactor);
+    return NS_OK;
+  }
+#endif
+
   if (mInstanceOwner->SendNativeEvents() &&
       NS_IS_PLUGIN_EVENT(anEvent)) {
     *anEventStatus = mInstanceOwner->ProcessEvent(*anEvent);
diff --git a/view/src/nsViewManager.cpp b/view/src/nsViewManager.cpp
index f163fda77482..fce825d8288d 100644
--- a/view/src/nsViewManager.cpp
+++ b/view/src/nsViewManager.cpp
@@ -751,7 +751,8 @@ nsresult nsViewManager::DispatchEvent(nsGUIEvent *aEvent, nsIView* aView, nsEven
        NS_IS_IME_RELATED_EVENT(aEvent) ||
        NS_IS_NON_RETARGETED_PLUGIN_EVENT(aEvent) ||
        aEvent->message == NS_PLUGIN_ACTIVATE ||
-       aEvent->message == NS_PLUGIN_FOCUS)) {
+       aEvent->message == NS_PLUGIN_FOCUS ||
+       aEvent->message == NS_PLUGIN_RESOLUTION_CHANGED)) {
     while (view && !view->GetFrame()) {
       view = view->GetParent();
     }
diff --git a/widget/cocoa/nsChildView.mm b/widget/cocoa/nsChildView.mm
index 2f2158a6dec3..f8c97fc301aa 100644
--- a/widget/cocoa/nsChildView.mm
+++ b/widget/cocoa/nsChildView.mm
@@ -778,13 +778,18 @@ nsChildView::BackingScaleFactorChanged()
 
   mBackingScaleFactor = newScale;
 
-  if (!mWidgetListener || mWidgetListener->GetXULWindow()) {
-    return;
+  if (mWidgetListener && !mWidgetListener->GetXULWindow()) {
+    nsIPresShell* presShell = mWidgetListener->GetPresShell();
+    if (presShell) {
+      presShell->BackingScaleFactorChanged();
+    }
   }
 
-  nsIPresShell* presShell = mWidgetListener->GetPresShell();
-  if (presShell) {
-    presShell->BackingScaleFactorChanged();
+  if (IsPluginView()) {
+    nsEventStatus status = nsEventStatus_eIgnore;
+    nsGUIEvent guiEvent(true, NS_PLUGIN_RESOLUTION_CHANGED, this);
+    guiEvent.time = PR_IntervalNow();
+    DispatchEvent(&guiEvent, status);
   }
 }
 
diff --git a/widget/nsGUIEvent.h b/widget/nsGUIEvent.h
index ad09db94ffaf..772cfe241b6c 100644
--- a/widget/nsGUIEvent.h
+++ b/widget/nsGUIEvent.h
@@ -173,6 +173,11 @@ class nsHashKey;
 #define NS_MOZ_USER_IDLE                 (NS_WINDOW_START + 67)
 #define NS_MOZ_USER_ACTIVE               (NS_WINDOW_START + 68)
 
+// The resolution at which a plugin should draw has changed, for
+// example as the result of changing from a HiDPI mode to a non-
+// HiDPI mode.
+#define NS_PLUGIN_RESOLUTION_CHANGED     (NS_WINDOW_START + 69)
+
 #define NS_MOUSE_MESSAGE_START          300
 #define NS_MOUSE_MOVE                   (NS_MOUSE_MESSAGE_START)
 #define NS_MOUSE_BUTTON_UP              (NS_MOUSE_MESSAGE_START + 1)
@@ -1778,7 +1783,8 @@ inline bool NS_IsEventUsingCoordinates(nsEvent* aEvent)
   return !NS_IS_KEY_EVENT(aEvent) && !NS_IS_IME_RELATED_EVENT(aEvent) &&
          !NS_IS_CONTEXT_MENU_KEY(aEvent) && !NS_IS_ACTIVATION_EVENT(aEvent) &&
          !NS_IS_PLUGIN_EVENT(aEvent) &&
-         !NS_IS_CONTENT_COMMAND_EVENT(aEvent);
+         !NS_IS_CONTENT_COMMAND_EVENT(aEvent) &&
+         aEvent->message != NS_PLUGIN_RESOLUTION_CHANGED;
 }
 
 /**