Backed out changeset b9b2895b11a3 (bug 1397426)

--HG--
extra : rebase_source : 8fada9f53beffaada9f16122efe5d9570d422e6c

browser/base/content/tabbrowser.xml

@@ -4438,7 +4438,8 @@
 
               let tab = this.requestedTab;
               let browser = tab.linkedBrowser;
-              let tabIsLoaded = browser.renderingLayers;
+              let tabIsLoaded = !browser.isRemoteBrowser ||
+                                browser.frameLoader.tabParent.hasPresented;
 
               if (!this.minimizedOrFullyOccluded) {
                 this.log("Initial tab is loaded?: " + tabIsLoaded);
@@ -4860,13 +4861,6 @@
             // Fires when the layers become available for a tab.
             onLayersReady(browser) {
               let tab = this.tabbrowser.getTabForBrowser(browser);
-              if (!tab) {
-                // We probably got a layer update from a tab that got before
-                // the switcher was created, or for browser that's not being
-                // tracked by the async tab switcher (like the preloaded about:newtab).
-                return;
-              }
-
               this.logState(`onLayersReady(${tab._tPos}, ${browser.isRemoteBrowser})`);
 
               this.assert(this.getTabState(tab) == this.STATE_LOADING ||

dom/ipc/TabChild.cpp

@@ -428,7 +428,7 @@ TabChild::TabChild(nsIContentChild* aManager,
   , mDidLoadURLInit(false)
   , mAwaitingLA(false)
   , mSkipKeyPress(false)
-  , mLayerObserverEpoch(1)
+  , mLayerObserverEpoch(0)
 #if defined(XP_WIN) && defined(ACCESSIBILITY)
   , mNativeWindowHandle(0)
 #endif
@@ -2937,9 +2937,6 @@ TabChild::InitRenderingState(const TextureFactoryIdentifier& aTextureFactoryIden
       ImageBridgeChild::IdentifyCompositorTextureHost(mTextureFactoryIdentifier);
       gfx::VRManagerChild::IdentifyTextureHost(mTextureFactoryIdentifier);
       InitAPZState();
-      RefPtr<LayerManager> lm = mPuppetWidget->GetLayerManager();
-      MOZ_ASSERT(lm);
-      lm->SetLayerObserverEpoch(mLayerObserverEpoch);
     } else {
       NS_WARNING("Fallback to BasicLayerManager");
       mLayersConnected = Some(false);
@@ -3053,14 +3050,7 @@ TabChild::MakeHidden()
     return;
   }
 
-  // Due to the nested event loop in ContentChild::ProvideWindowCommon,
-  // it's possible to be told to become hidden before we're finished
-  // setting up a layer manager. We should skip clearing cached layers
-  // in that case, since doing so might accidentally put is into
-  // BasicLayers mode.
-  if (mPuppetWidget && mPuppetWidget->HasLayerManager()) {
-    ClearCachedResources();
-  }
+  ClearCachedResources();
 
   // Hide all plugins in this tab.
   if (nsCOMPtr<nsIPresShell> shell = GetPresShell()) {
@@ -3565,7 +3555,7 @@ TabChild::GetOuterRect()
 void
 TabChild::ForcePaint(uint64_t aLayerObserverEpoch)
 {
-  if (!IPCOpen() || !mPuppetWidget || !mPuppetWidget->HasLayerManager()) {
+  if (!IPCOpen()) {
     // Don't bother doing anything now. Better to wait until we receive the
     // message on the PContent channel.
     return;

dom/ipc/TabParent.cpp

@@ -171,9 +171,9 @@ TabParent::TabParent(nsIContentParent* aManager,
 #ifdef DEBUG
   , mActiveSupressDisplayportCount(0)
 #endif
-  , mLayerTreeEpoch(1)
+  , mLayerTreeEpoch(0)
   , mPreserveLayers(false)
-  , mRenderLayers(true)
+  , mRenderLayers(false)
   , mHasLayers(false)
   , mHasPresented(false)
   , mHasBeforeUnload(false)