Bug 1157941 - If the current PresShell is suppressed, paint the old one if it is available r=tn

view/nsView.cpp

@@ -90,6 +90,10 @@ nsView::~nsView()
     mParent->RemoveChild(this);
   }
 
+  if (mPreviousWindow) {
+    mPreviousWindow->SetPreviouslyAttachedWidgetListener(nullptr);
+  }
+
   // Destroy and release the widget
   DestroyWidget();
 
@@ -722,6 +726,18 @@ nsresult nsView::DetachFromTopLevelWidget()
   NS_PRECONDITION(mWindow, "null mWindow for DetachFromTopLevelWidget!");
 
   mWindow->SetAttachedWidgetListener(nullptr);
+  nsIWidgetListener* listener = mWindow->GetPreviouslyAttachedWidgetListener();
+
+  if (listener && listener->GetView()) {
+    // Ensure the listener doesn't think it's being used anymore
+    listener->GetView()->SetPreviousWidget(nullptr);
+  }
+
+  // If the new view's frame is paint suppressed then the window
+  // will want to use us instead until that's done
+  mWindow->SetPreviouslyAttachedWidgetListener(this);
+
+  mPreviousWindow = mWindow;
   mWindow = nullptr;
 
   mWidgetIsTopLevel = false;
@@ -1096,3 +1112,9 @@ nsView::HandleEvent(WidgetGUIEvent* aEvent,
 
   return result;
 }
+
+bool
+nsView::IsPrimaryFramePaintSuppressed()
+{
+  return mFrame ? mFrame->PresContext()->PresShell()->IsPaintingSuppressed() : false;
+}

view/nsView.h

@@ -281,6 +281,14 @@ public:
    */
   nsIWidget* GetWidget() const { return mWindow; }
 
+  /**
+   * The widget which we have attached a listener to can also have a "previous"
+   * listener set on it. This is to keep track of the last nsView when navigating
+   * to a new one so that we can continue to paint that if the new one isn't ready
+   * yet.
+   */
+  void SetPreviousWidget(nsIWidget* aWidget) { mPreviousWindow = aWidget; }
+
   /**
    * Returns true if the view has a widget associated with it.
    */
@@ -383,6 +391,8 @@ public:
   nsPoint GetOffsetTo(const nsView* aOther, const int32_t aAPD) const;
   nsIWidget* GetNearestWidget(nsPoint* aOffset, const int32_t aAPD) const;
 
+  bool IsPrimaryFramePaintSuppressed();
+
 private:
   explicit nsView(nsViewManager* aViewManager = nullptr,
                   nsViewVisibility aVisibility = nsViewVisibility_kShow);
@@ -450,6 +460,7 @@ private:
   nsViewManager    *mViewManager;
   nsView           *mParent;
   nsCOMPtr<nsIWidget> mWindow;
+  nsCOMPtr<nsIWidget> mPreviousWindow;
   nsView           *mNextSibling;
   nsView           *mFirstChild;
   nsIFrame         *mFrame;

view/nsViewManager.cpp

@@ -440,11 +440,20 @@ nsViewManager::ProcessPendingUpdatesPaint(nsIWidget* aWidget)
       }
     }
     nsView* view = nsView::GetViewFor(aWidget);
+
     if (!view) {
       NS_ERROR("FlushDelayedResize destroyed the nsView?");
       return;
     }
 
+    nsIWidgetListener* previousListener = aWidget->GetPreviouslyAttachedWidgetListener();
+
+    if (previousListener &&
+        previousListener != view &&
+        view->IsPrimaryFramePaintSuppressed()) {
+      return;
+    }
+
     if (mPresShell) {
 #ifdef MOZ_DUMP_PAINTING
       if (nsLayoutUtils::InvalidationDebuggingIsEnabled()) {
@@ -1149,3 +1158,4 @@ nsViewManager::InvalidateHierarchy()
     }
   }
 }
+

widget/PuppetWidget.cpp

@@ -217,7 +217,14 @@ PuppetWidget::Resize(double aWidth,
     InvalidateRegion(this, dirty);
   }
 
+  // call WindowResized() on both the current listener, and possibly
+  // also the previous one if we're in a state where we're drawing that one
+  // because the current one is paint suppressed
   if (!oldBounds.IsEqualEdges(mBounds) && mAttachedWidgetListener) {
+    if (GetCurrentWidgetListener() &&
+        GetCurrentWidgetListener() != mAttachedWidgetListener) {
+      GetCurrentWidgetListener()->WindowResized(this, mBounds.width, mBounds.height);
+    }
     mAttachedWidgetListener->WindowResized(this, mBounds.width, mBounds.height);
   }
 
@@ -313,8 +320,8 @@ PuppetWidget::DispatchEvent(WidgetGUIEvent* event, nsEventStatus& aStatus)
 
   aStatus = nsEventStatus_eIgnore;
 
-  if (mAttachedWidgetListener) {
-    aStatus = mAttachedWidgetListener->HandleEvent(event, mUseAttachedEvents);
+  if (GetCurrentWidgetListener()) {
+    aStatus = GetCurrentWidgetListener()->HandleEvent(event, mUseAttachedEvents);
   }
 
   return NS_OK;
@@ -914,7 +921,7 @@ PuppetWidget::Paint()
 {
   MOZ_ASSERT(!mDirtyRegion.IsEmpty(), "paint event logic messed up");
 
-  if (!mAttachedWidgetListener)
+  if (!GetCurrentWidgetListener())
     return NS_OK;
 
   nsIntRegion region = mDirtyRegion;
@@ -923,9 +930,9 @@ PuppetWidget::Paint()
   mDirtyRegion.SetEmpty();
   mPaintTask.Revoke();
 
-  mAttachedWidgetListener->WillPaintWindow(this);
+  GetCurrentWidgetListener()->WillPaintWindow(this);
 
-  if (mAttachedWidgetListener) {
+  if (GetCurrentWidgetListener()) {
 #ifdef DEBUG
     debug_DumpPaintEvent(stderr, this, region,
                          nsAutoCString("PuppetWidget"), 0);
@@ -942,15 +949,15 @@ PuppetWidget::Paint()
       ctx->Clip();
       AutoLayerManagerSetup setupLayerManager(this, ctx,
                                               BufferMode::BUFFER_NONE);
-      mAttachedWidgetListener->PaintWindow(this, region);
+      GetCurrentWidgetListener()->PaintWindow(this, region);
       if (mTabChild) {
         mTabChild->NotifyPainted();
       }
     }
   }
 
-  if (mAttachedWidgetListener) {
-    mAttachedWidgetListener->DidPaintWindow();
+  if (GetCurrentWidgetListener()) {
+    GetCurrentWidgetListener()->DidPaintWindow();
   }
 
   return NS_OK;
@@ -1251,5 +1258,20 @@ PuppetScreenManager::GetSystemDefaultScale(float *aDefaultScale)
   return NS_OK;
 }
 
+nsIWidgetListener*
+PuppetWidget::GetCurrentWidgetListener()
+{
+  if (!mPreviouslyAttachedWidgetListener ||
+      !mAttachedWidgetListener) {
+    return mAttachedWidgetListener;
+  }
+
+  if (mAttachedWidgetListener->GetView()->IsPrimaryFramePaintSuppressed()) {
+    return mPreviouslyAttachedWidgetListener;
+  }
+
+  return mAttachedWidgetListener;
+}
+
 }  // namespace widget
 }  // namespace mozilla

widget/PuppetWidget.h

@@ -274,6 +274,8 @@ private:
   bool GetCaretRect(mozilla::LayoutDeviceIntRect& aCaretRect, uint32_t aCaretOffset);
   uint32_t GetCaretOffset();
 
+  nsIWidgetListener* GetCurrentWidgetListener();
+
   class PaintTask : public nsRunnable {
   public:
     NS_DECL_NSIRUNNABLE

widget/nsBaseWidget.cpp

@@ -146,6 +146,7 @@ NS_IMPL_ISUPPORTS(nsBaseWidget, nsIWidget, nsISupportsWeakReference)
 nsBaseWidget::nsBaseWidget()
 : mWidgetListener(nullptr)
 , mAttachedWidgetListener(nullptr)
+, mPreviouslyAttachedWidgetListener(nullptr)
 , mLayerManager(nullptr)
 , mCompositorVsyncDispatcher(nullptr)
 , mCursor(eCursor_standard)
@@ -399,6 +400,16 @@ nsIWidgetListener* nsBaseWidget::GetAttachedWidgetListener()
    return mAttachedWidgetListener;
  }
 
+nsIWidgetListener* nsBaseWidget::GetPreviouslyAttachedWidgetListener()
+ {
+   return mPreviouslyAttachedWidgetListener;
+ }
+
+void nsBaseWidget::SetPreviouslyAttachedWidgetListener(nsIWidgetListener* aListener)
+ {
+   mPreviouslyAttachedWidgetListener = aListener;
+ }
+
 void nsBaseWidget::SetAttachedWidgetListener(nsIWidgetListener* aListener)
  {
    mAttachedWidgetListener = aListener;

widget/nsBaseWidget.h

@@ -231,6 +231,8 @@ public:
   NS_IMETHOD              AttachViewToTopLevel(bool aUseAttachedEvents) override;
   virtual nsIWidgetListener* GetAttachedWidgetListener() override;
   virtual void               SetAttachedWidgetListener(nsIWidgetListener* aListener) override;
+  virtual nsIWidgetListener* GetPreviouslyAttachedWidgetListener() override;
+  virtual void               SetPreviouslyAttachedWidgetListener(nsIWidgetListener* aListener) override;
   NS_IMETHOD_(TextEventDispatcher*) GetTextEventDispatcher() override final;
 
   // Helper function for dispatching events which are not processed by APZ,
@@ -479,6 +481,7 @@ protected:
 
   nsIWidgetListener* mWidgetListener;
   nsIWidgetListener* mAttachedWidgetListener;
+  nsIWidgetListener* mPreviouslyAttachedWidgetListener;
   nsRefPtr<LayerManager> mLayerManager;
   nsRefPtr<CompositorChild> mCompositorChild;
   nsRefPtr<CompositorParent> mCompositorParent;

widget/nsIWidget.h

@@ -119,8 +119,8 @@ typedef void* nsNativeWidget;
 #define NS_NATIVE_PLUGIN_ID            105
 
 #define NS_IWIDGET_IID \
-{ 0x53376F57, 0xF081, 0x4949, \
-  { 0xB5, 0x5E, 0x87, 0xEF, 0x6A, 0xE9, 0xE3, 0x5A } };
+{ 0x483BF75C, 0xF909, 0x45C3, \
+  { 0x95, 0xBE, 0x41, 0x89, 0xDB, 0xCE, 0x2E, 0x13 } };
 
 /*
  * Window shadow styles
@@ -941,6 +941,8 @@ class nsIWidget : public nsISupports {
      */
     virtual void SetAttachedWidgetListener(nsIWidgetListener* aListener) = 0;
     virtual nsIWidgetListener* GetAttachedWidgetListener() = 0;
+    virtual void SetPreviouslyAttachedWidgetListener(nsIWidgetListener* aListener) = 0;
+    virtual nsIWidgetListener* GetPreviouslyAttachedWidgetListener() = 0;
 
     /**
      * Accessor functions to get and set the listener which handles various