Backout changeset e794d5f88e0c (bug 539356) because of performance and correctness regressions

layout/base/nsRefreshDriver.cpp

@@ -415,8 +415,7 @@ nsRefreshDriver::Notify(nsITimer *aTimer)
     printf("Starting ProcessPendingUpdates\n");
 #endif
     mViewManagerFlushIsPending = false;
-    bool skippedFlush = mPresContext->GetPresShell()->GetViewManager()->ProcessPendingUpdates();
-    mViewManagerFlushIsPending |= skippedFlush;
+    mPresContext->GetPresShell()->GetViewManager()->ProcessPendingUpdates();
 #ifdef DEBUG_INVALIDATIONS
     printf("Ending ProcessPendingUpdates\n");
 #endif

view/public/nsIViewManager.h

@@ -296,11 +296,8 @@ public:
   /**
    * Flush the accumulated dirty region to the widget and update widget
    * geometry.
-   *
-   * @param True if a paint was skipped due to throttling and this
-   * should be called again after a delay.
    */
-  virtual bool ProcessPendingUpdates()=0;
+  virtual void ProcessPendingUpdates()=0;
 
   /**
    * Just update widget geometry without flushing the dirty region

view/src/nsView.cpp

@@ -176,8 +176,6 @@ nsView::nsView(nsViewManager* aViewManager, nsViewVisibility aVisibility)
   mDirtyRegion = nsnull;
   mDeletionObserver = nsnull;
   mWidgetIsTopLevel = false;
-  mPendingRefresh = false;
-  mSkippedPaints = 0;
 }
 
 void nsView::DropMouseGrabbing()

view/src/nsView.h

@@ -162,13 +162,6 @@ public:
   nsPoint GetOffsetTo(const nsView* aOther, const PRInt32 aAPD) const;
   nsIWidget* GetNearestWidget(nsPoint* aOffset, const PRInt32 aAPD) const;
 
-  void SetPendingRefresh(bool aPending) { mPendingRefresh = aPending; }
-  bool PendingRefresh() { return mPendingRefresh; }
-
-  void SkippedPaint() { mSkippedPaints++; }
-  void ClearSkippedPaints() { mSkippedPaints = 0; }
-  PRUint32 SkippedPaints() { return mSkippedPaints; }
-
 protected:
   // Do the actual work of ResetWidgetBounds, unconditionally.  Don't
   // call this method if we have no widget.
@@ -176,15 +169,6 @@ protected:
 
   nsRegion*    mDirtyRegion;
 
-  // True if the view has invalidate scheduled with the widget
-  // and is waiting for nsViewManager::Refresh to be called.
-  bool mPendingRefresh;
-
-  // True if a paint event was skipped while mPendingRefresh was
-  // true, and a new one should be scheduled once we get
-  // nsViewManager::Refresh called.
-  PRUint32 mSkippedPaints;
-
 private:
   void InitializeWindow(bool aEnableDragDrop, bool aResetVisibility);
 };

view/src/nsViewManager.cpp

@@ -301,11 +301,6 @@ void nsViewManager::Refresh(nsView *aView, const nsIntRegion& aRegion,
                             bool aWillSendDidPaint)
 {
   NS_ASSERTION(aView->GetViewManager() == this, "wrong view manager");
-  aView->SetPendingRefresh(false);
-  if (aView->SkippedPaints()) {
-    RootViewManager()->GetPresShell()->ScheduleViewManagerFlush(true);
-    aView->ClearSkippedPaints();
-  }
 
   // damageRegion is the damaged area, in twips, relative to the view origin
   nsRegion damageRegion = aRegion.ToAppUnits(AppUnitsPerDevPixel());
@@ -357,14 +352,14 @@ void nsViewManager::Refresh(nsView *aView, const nsIntRegion& aRegion,
   }
 }
 
-bool nsViewManager::ProcessPendingUpdatesForView(nsView* aView,
+void nsViewManager::ProcessPendingUpdatesForView(nsView* aView,
                                                  bool aFlushDirtyRegion)
 {
   NS_ASSERTION(IsRootVM(), "Updates will be missed");
 
   // Protect against a null-view.
   if (!aView) {
-    return false;
+    return;
   }
 
   if (aView->HasWidget()) {
@@ -372,10 +367,9 @@ bool nsViewManager::ProcessPendingUpdatesForView(nsView* aView,
   }
 
   // process pending updates in child view.
-  bool skipped = false;
   for (nsView* childView = aView->GetFirstChild(); childView;
        childView = childView->GetNextSibling()) {
-    skipped |= ProcessPendingUpdatesForView(childView, aFlushDirtyRegion);
+    ProcessPendingUpdatesForView(childView, aFlushDirtyRegion);
   }
 
   // Push out updates after we've processed the children; ensures that
@@ -383,28 +377,18 @@ bool nsViewManager::ProcessPendingUpdatesForView(nsView* aView,
   if (aFlushDirtyRegion) {
     nsIWidget *widget = aView->GetWidget();
     if (widget && widget->NeedsPaint()) {
-      if (aView->PendingRefresh() && aView->SkippedPaints() < 5) {
-        aView->SkippedPaint();
-        skipped = true;
-      } else {
-        aView->ClearSkippedPaints();
-        aView->SetPendingRefresh(false);
-        widget->SetNeedsPaint(false);
-        SetPainting(true);
+      widget->SetNeedsPaint(false);
 #ifdef DEBUG_INVALIDATIONS
-        printf("---- PAINT START ----PresShell(%p), nsView(%p), nsIWidget(%p)\n", mPresShell, aView, widget);
+      printf("---- PAINT START ----PresShell(%p), nsView(%p), nsIWidget(%p)\n", mPresShell, aView, widget);
 #endif
-        nsAutoScriptBlocker scriptBlocker;
-        mPresShell->Paint(aView, nsRegion(), nsIPresShell::PaintType_NoComposite, false);
+      nsAutoScriptBlocker scriptBlocker;
+      mPresShell->Paint(aView, nsRegion(), nsIPresShell::PaintType_NoComposite, false);
 #ifdef DEBUG_INVALIDATIONS
-        printf("---- PAINT END ----\n");
+      printf("---- PAINT END ----\n");
 #endif
-        SetPainting(false);
-      }
     }
     FlushDirtyRegionToWidget(aView);
   }
-  return skipped;
 }
 
 void nsViewManager::FlushDirtyRegionToWidget(nsView* aView)
@@ -447,7 +431,7 @@ nsViewManager::PostPendingUpdate()
 {
   nsViewManager* rootVM = RootViewManager();
   rootVM->mHasPendingWidgetGeometryChanges = true;
-  if (rootVM->mPresShell && !rootVM->IsPainting()) {
+  if (rootVM->mPresShell) {
     rootVM->mPresShell->ScheduleViewManagerFlush(nsIFrame::PAINT_COMPOSITE_ONLY);
   }
 }
@@ -530,7 +514,6 @@ nsViewManager::InvalidateWidgetArea(nsView *aWidgetView,
   leftOver.Sub(aDamagedRegion, children);
 
   if (!leftOver.IsEmpty()) {
-    aWidgetView->SetPendingRefresh(true);
     const nsRect* r;
     for (nsRegionRectIterator iter(leftOver); (r = iter.Next());) {
       nsIntRect bounds = ViewToWidget(aWidgetView, *r);
@@ -1317,15 +1300,16 @@ nsViewManager::IsPainting(bool& aIsPainting)
   return NS_OK;
 }
 
-bool
+void
 nsViewManager::ProcessPendingUpdates()
 {
   if (!IsRootVM()) {
-    return RootViewManager()->ProcessPendingUpdates();
+    RootViewManager()->ProcessPendingUpdates();
+    return;
   }
 
   mPresShell->GetPresContext()->RefreshDriver()->RevokeViewManagerFlush();
-  return ProcessPendingUpdatesForView(mRootView, true);
+  ProcessPendingUpdatesForView(mRootView, true);
 }
 
 void

view/src/nsViewManager.h

@@ -105,7 +105,7 @@ public:
   /* Update the cached RootViewManager pointer on this view manager. */
   void InvalidateHierarchy();
 
-  virtual bool ProcessPendingUpdates();
+  virtual void ProcessPendingUpdates();
   virtual void UpdateWidgetGeometry();
 
 protected:
@@ -114,10 +114,7 @@ protected:
 private:
 
   void FlushPendingInvalidates();
-  /* Returns true if we skipped painting a view and we should try
-   * again later.
-   */
-  bool ProcessPendingUpdatesForView(nsView *aView,
+  void ProcessPendingUpdatesForView(nsView *aView,
                                     bool aFlushDirtyRegion = true);
   void FlushDirtyRegionToWidget(nsView* aView);
   /**