Bug 539356 - Part 11 - Reimplement empty transactions. r=roc

layout/base/nsIPresShell.h

@@ -1229,7 +1229,16 @@ public:
    * root pres shell.
    */
   virtual void DidPaint() = 0;
-  virtual void ScheduleViewManagerFlush() = 0;
+
+  /**
+   * Ensures that the refresh driver is running, and schedules a view 
+   * manager flush on the next tick.
+   *
+   * @param aFlags nsIFrame::PAINT_COMPOSITE_ONLY : No changes have 
+   * been made that require a layer tree update, so only schedule a 
+   * layer tree composite.
+   */
+  virtual void ScheduleViewManagerFlush(PRUint32 aFlags = 0) = 0;
   virtual void ClearMouseCaptureOnView(nsIView* aView) = 0;
   virtual bool IsVisible() = 0;
   virtual void DispatchSynthMouseMove(nsGUIEvent *aEvent, bool aFlushOnHoverChange) = 0;

layout/base/nsPresShell.cpp

@@ -170,6 +170,7 @@
 #include "sampler.h"
 
 #include "Layers.h"
+#include "LayerTreeInvalidation.h"
 #include "nsAsyncDOMEvent.h"
 
 #ifdef NS_FUNCTION_TIMER
@@ -3374,11 +3375,14 @@ PresShell::GetRectVisibility(nsIFrame* aFrame,
 }
 
 void
-PresShell::ScheduleViewManagerFlush()
+PresShell::ScheduleViewManagerFlush(PRUint32 aFlags)
 {
   nsPresContext* presContext = GetPresContext();
   if (presContext) {
     presContext->RefreshDriver()->ScheduleViewManagerFlush();
+    if (!(aFlags & nsIFrame::PAINT_COMPOSITE_ONLY)) {
+      mPaintRequired = true;
+    }
   }
   if (mDocument) {
     mDocument->SetNeedLayoutFlush();
@@ -5238,7 +5242,7 @@ PresShell::Paint(nsIView*           aViewToPaint,
     // need to be updated. Do not try to do an empty transaction on
     // a non-retained layer manager (like the BasicLayerManager that
     // draws the window title bar on Mac), because a) it won't work
-    // and b) below we don't want to clear NS_FRAME_UPDATE_LAYER_TREE,
+    // and b) below we don't want to clear mPaintRequired,
     // that will cause us to forget to update the real layer manager!
     if (aType == PaintType_Composite) {
       if (layerManager->HasShadowManager()) {
@@ -5253,7 +5257,40 @@ PresShell::Paint(nsIView*           aViewToPaint,
       layerManager->BeginTransaction();
     }
 
-    frame->RemoveStateBits(NS_FRAME_UPDATE_LAYER_TREE);
+    if (!mPaintRequired) {
+      NotifySubDocInvalidationFunc computeInvalidFunc =
+        presContext->MayHavePaintEventListenerInSubDocument() ? nsPresContext::NotifySubDocInvalidation : 0;
+      bool computeInvalidRect = computeInvalidFunc ||
+                                (layerManager->GetBackendType() == LayerManager::LAYERS_BASIC);
+
+      nsAutoPtr<LayerProperties> props(computeInvalidRect ? 
+                                         LayerProperties::CloneFrom(layerManager->GetRoot()) : 
+                                         nsnull);
+
+      if (layerManager->EndEmptyTransaction()) {
+        nsIntRect invalid;
+        if (props) {
+          invalid = props->ComputeDifferences(layerManager->GetRoot(), computeInvalidFunc);
+        }
+        if (!invalid.IsEmpty()) {
+          if (props) {
+            nsRect rect(presContext->DevPixelsToAppUnits(invalid.x),
+                        presContext->DevPixelsToAppUnits(invalid.y),
+                        presContext->DevPixelsToAppUnits(invalid.width),
+                        presContext->DevPixelsToAppUnits(invalid.height));
+            aViewToPaint->GetViewManager()->InvalidateViewNoSuppression(aViewToPaint, rect);
+            presContext->NotifyInvalidation(invalid, 0);
+          } else {
+            aViewToPaint->GetViewManager()->InvalidateView(aViewToPaint);
+          }
+        }
+    
+        frame->UpdatePaintCountForPaintedPresShells();
+        presContext->NotifyDidPaintForSubtree();
+        return;
+      }
+    }
+    mPaintRequired = false;
   } else {
     layerManager->BeginTransaction();
   }

layout/base/nsPresShell.h

@@ -199,7 +199,7 @@ public:
   virtual bool ShouldIgnoreInvalidation();
   virtual void WillPaint(bool aWillSendDidPaint);
   virtual void DidPaint();
-  virtual void ScheduleViewManagerFlush();
+  virtual void ScheduleViewManagerFlush(PRUint32 aFlags = 0);
   virtual void DispatchSynthMouseMove(nsGUIEvent *aEvent, bool aFlushOnHoverChange);
   virtual void ClearMouseCaptureOnView(nsIView* aView);
   virtual bool IsVisible();
@@ -768,6 +768,12 @@ protected:
   bool                      mNoDelayedMouseEvents : 1;
   bool                      mNoDelayedKeyEvents : 1;
 
+  // False if calls to Paint with the retaining manager can be handled
+  // with an empty transaction, True if we require painting and a layer
+  // tree update.
+  bool                      mPaintRequired : 1;
+
+
   // We've been disconnected from the document.  We will refuse to paint the
   // document until either our timer fires or all frames are constructed.
   bool                      mIsDocumentGone : 1;

layout/generic/nsFrame.cpp

@@ -4651,7 +4651,7 @@ nsIFrame::IsInvalid()
 }
 
 void
-nsIFrame::SchedulePaint()
+nsIFrame::SchedulePaint(PRUint32 aFlags)
 {
   nsPresContext *pres = PresContext()->GetRootPresContext();
   if (HasAnyStateBits(NS_FRAME_IN_POPUP) || !pres) {
@@ -4662,7 +4662,7 @@ nsIFrame::SchedulePaint()
     }
     pres = displayRoot->PresContext();
   }
-  pres->PresShell()->ScheduleViewManagerFlush();
+  pres->PresShell()->ScheduleViewManagerFlush(aFlags);
 }
 
 Layer*
@@ -4686,7 +4686,7 @@ nsIFrame::InvalidateLayer(PRUint32 aDisplayItemKey, const nsIntRect* aDamageRect
     layer->SetInvalidRectToVisibleRegion();
   }
 
-  SchedulePaint();
+  SchedulePaint(PAINT_COMPOSITE_ONLY);
   return layer;
 }
 

layout/generic/nsIFrame.h

@@ -242,12 +242,6 @@ typedef PRUint64 nsFrameState;
 // Frame's overflow area was clipped by the 'clip' property.
 #define NS_FRAME_HAS_CLIP                           NS_FRAME_STATE_BIT(35)
 
-// Frame is a display root and the retained layer tree needs to be updated
-// at the next paint via display list construction.
-// Only meaningful for display roots, so we don't really need a global state
-// bit; we could free up this bit with a little extra complexity.
-#define NS_FRAME_UPDATE_LAYER_TREE                  NS_FRAME_STATE_BIT(36)
-
 // Frame can accept absolutely positioned children.
 #define NS_FRAME_HAS_ABSPOS_CHILDREN                NS_FRAME_STATE_BIT(37)
 
@@ -2159,8 +2153,15 @@ public:
    * The view manager flush will update the layer tree, repaint any 
    * invalid areas in the layer tree and schedule a layer tree
    * composite operation to display the layer tree.
+   *
+   * @param aFlags PAINT_COMPOSITE_ONLY : No changes have been made
+   * that require a layer tree update, so only schedule a layer
+   * tree composite.
    */
-  void SchedulePaint();
+  enum {
+    PAINT_COMPOSITE_ONLY
+  };
+  void SchedulePaint(PRUint32 aFlags = 0);
 
   /**
    * Checks if the layer tree includes a dedicated layer for this 

view/src/nsViewManager.cpp

@@ -433,7 +433,7 @@ nsViewManager::PostPendingUpdate()
   nsViewManager* rootVM = RootViewManager();
   rootVM->mHasPendingWidgetGeometryChanges = true;
   if (rootVM->mPresShell) {
-    rootVM->mPresShell->ScheduleViewManagerFlush();
+    rootVM->mPresShell->ScheduleViewManagerFlush(nsIFrame::PAINT_COMPOSITE_ONLY);
   }
 }