Bug 1133237 - When transitioning from a shadow layer tree that has plugins to a tree that does not, make sure the old plugins get hidden properly. r=roc

gfx/layers/ipc/CompositorChild.cpp

@@ -258,6 +258,20 @@ CompositorChild::RecvUpdatePluginConfigurations(const nsIntPoint& aContentOffset
 #endif // !defined(XP_WIN) && !defined(MOZ_WIDGET_GTK)
 }
 
+bool
+CompositorChild::RecvUpdatePluginVisibility(nsTArray<uintptr_t>&& aVisibleIdList)
+{
+#if !defined(XP_WIN) && !defined(MOZ_WIDGET_GTK)
+  NS_NOTREACHED("CompositorChild::RecvUpdatePluginVisibility calls "
+                "unexpected on this platform.");
+  return false;
+#else
+  MOZ_ASSERT(NS_IsMainThread());
+  nsIWidget::UpdateRegisteredPluginWindowVisibility(aVisibleIdList);
+  return true;
+#endif // !defined(XP_WIN) && !defined(MOZ_WIDGET_GTK)
+}
+
 bool
 CompositorChild::RecvDidComposite(const uint64_t& aId, const uint64_t& aTransactionId)
 {

gfx/layers/ipc/CompositorChild.h

@@ -80,6 +80,9 @@ public:
                                  const nsIntRegion& aVisibleRegion,
                                  nsTArray<PluginWindowData>&& aPlugins) MOZ_OVERRIDE;
 
+  virtual bool
+  RecvUpdatePluginVisibility(nsTArray<uintptr_t>&& aWindowList) MOZ_OVERRIDE;
+
   /**
    * Request that the parent tell us when graphics are ready on GPU.
    * When we get that message, we bounce it to the TabParent via

gfx/layers/ipc/CompositorParent.cpp

@@ -1749,7 +1749,7 @@ CrossProcessCompositorParent::ShadowLayersUpdated(
 
   // Cache the plugin data for this remote layer tree
   state->mPluginData = aPlugins;
-  state->mUpdatedPluginDataAvailable = !!state->mPluginData.Length();
+  state->mUpdatedPluginDataAvailable = true;
 
   state->mParent->NotifyShadowTreeTransaction(id, aIsFirstPaint, aScheduleComposite,
       aPaintSequenceNumber, aIsRepeatTransaction);
@@ -1763,12 +1763,13 @@ CrossProcessCompositorParent::ShadowLayersUpdated(
   aLayerTree->SetPendingTransactionId(aTransactionId);
 }
 
+#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
 // Sends plugin window state changes to the main thread
 static void
 UpdatePluginWindowState(uint64_t aId)
 {
   CompositorParent::LayerTreeState& lts = sIndirectLayerTrees[aId];
-  if (!lts.mPluginData.Length()) {
+  if (!lts.mPluginData.Length() && !lts.mUpdatedPluginDataAvailable) {
     return;
   }
 
@@ -1779,8 +1780,17 @@ UpdatePluginWindowState(uint64_t aId)
   bool shouldHidePlugin = (!lts.mRoot ||
                            !lts.mRoot->GetParent()) &&
                           !lts.mUpdatedPluginDataAvailable;
-
   if (shouldComposePlugin) {
+    if (!lts.mPluginData.Length()) {
+      // We will pass through here in cases where the previous shadow layer
+      // tree contained visible plugins and the new tree does not. All we need
+      // to do here is hide the plugins for the old tree, so don't waste time
+      // calculating clipping.
+      nsTArray<uintptr_t> aVisibleIdList;
+      unused << lts.mParent->SendUpdatePluginVisibility(aVisibleIdList);
+      return;
+    }
+
     // Retrieve the offset and visible region of the layer that hosts
     // the plugins, CompositorChild needs these in calculating proper
     // plugin clipping.
@@ -1818,6 +1828,7 @@ UpdatePluginWindowState(uint64_t aId)
     lts.mPluginData.Clear();
   }
 }
+#endif // #if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
 
 void
 CrossProcessCompositorParent::DidComposite(uint64_t aId)
@@ -1828,7 +1839,9 @@ CrossProcessCompositorParent::DidComposite(uint64_t aId)
     unused << SendDidComposite(aId, layerTree->GetPendingTransactionId());
     layerTree->SetPendingTransactionId(0);
   }
+#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
   UpdatePluginWindowState(aId);
+#endif
 }
 
 void

gfx/layers/ipc/PCompositor.ipdl

@@ -66,6 +66,12 @@ child:
                                    nsIntRegion aVisibleRegion,
                                    PluginWindowData[] aPlugins);
 
+  /**
+   * Sets the list of currently visible plugin windows based on a
+   * list of plugin window ids.
+   */
+  async UpdatePluginVisibility(uintptr_t[] aVisibleIdList);
+
 parent:
   // Child sends the parent a request for fill ratio numbers.
   async RequestOverfill();