Bug 993930 - Do not assume TabChild::mInnerSize being (0, 0) means it's never been initialized. r=kats

dom/ipc/TabChild.cpp

@@ -147,12 +147,6 @@ TabChildBase::InitializeRootMetrics()
   mLastRootMetrics.SetScrollOffset(CSSPoint(0, 0));
 }
 
-bool
-TabChildBase::HasValidInnerSize()
-{
-  return (mInnerSize.width != 0) && (mInnerSize.height != 0);
-}
-
 void
 TabChildBase::SetCSSViewport(const CSSSize& aSize)
 {
@@ -696,6 +690,7 @@ TabChild::TabChild(ContentChild* aManager, const TabContext& aContext, uint32_t
   , mWaitingTouchListeners(false)
   , mIgnoreKeyPressEvent(false)
   , mActiveElementManager(new ActiveElementManager())
+  , mHasValidInnerSize(false)
 {
   if (!sActiveDurationMsSet) {
     Preferences::AddIntVarCache(&sActiveDurationMs,
@@ -1288,6 +1283,12 @@ TabChild::BrowserFrameProvideWindow(nsIDOMWindow* aOpener,
   return NS_OK;
 }
 
+bool
+TabChild::HasValidInnerSize()
+{
+  return mHasValidInnerSize;
+}
+
 #ifdef DEBUG
 PContentPermissionRequestChild*
 TabChild:: SendPContentPermissionRequestConstructor(PContentPermissionRequestChild* aActor,
@@ -1614,6 +1615,9 @@ TabChild::RecvUpdateDimensions(const nsRect& rect, const nsIntSize& size, const
 
     bool initialSizing = !HasValidInnerSize()
                       && (size.width != 0 && size.height != 0);
+    if (initialSizing) {
+      mHasValidInnerSize = true;
+    }
 
     mOrientation = orientation;
     mInnerSize = ScreenIntSize::FromUnknownSize(

dom/ipc/TabChild.h

@@ -205,7 +205,6 @@ protected:
 
     nsEventStatus DispatchWidgetEvent(WidgetGUIEvent& event);
 
-    bool HasValidInnerSize();
     void InitializeRootMetrics();
 
     mozilla::layers::FrameMetrics ProcessUpdateFrame(const mozilla::layers::FrameMetrics& aFrameMetrics);
@@ -522,6 +521,8 @@ private:
                               bool* aWindowIsNew,
                               nsIDOMWindow** aReturn);
 
+    bool HasValidInnerSize();
+
     class CachedFileDescriptorInfo;
     class CachedFileDescriptorCallbackRunnable;
 
@@ -560,6 +561,7 @@ private:
 
     bool mIgnoreKeyPressEvent;
     nsRefPtr<ActiveElementManager> mActiveElementManager;
+    bool mHasValidInnerSize;
 
     DISALLOW_EVIL_CONSTRUCTORS(TabChild);
 };