Bug 873944 - When we have OMTC, don't invalidate and wait for the widget paint event, just call DidPaint immediately. If we do get a widget paint event (from an OS initiated resize or similar), then block until the compositor has drawn the frame. r=roc

gfx/layers/Layers.h

@@ -475,6 +475,12 @@ public:
    */
   virtual void FlushRendering() { }
 
+  /**
+   * Checks if we need to invalidate the OS widget to trigger
+   * painting when updating this layer manager.
+   */
+  virtual bool NeedsWidgetInvalidation() { return true; }
+
   // We always declare the following logging symbols, because it's
   // extremely tricky to conditionally declare them.  However, for
   // ifndef MOZ_LAYERS_HAVE_LOG builds, they only have trivial

gfx/layers/client/ClientLayerManager.h

@@ -55,6 +55,8 @@ public:
 
   virtual void FlushRendering() MOZ_OVERRIDE;
 
+  virtual bool NeedsWidgetInvalidation() MOZ_OVERRIDE { return Compositor::GetBackend() == LAYERS_BASIC; }
+
   ShadowableLayer* Hold(Layer* aLayer);
 
   bool HasShadowManager() const { return ShadowLayerForwarder::HasShadowManager(); }

layout/base/nsDisplayList.cpp

@@ -1199,6 +1199,7 @@ void nsDisplayList::PaintForFrame(nsDisplayListBuilder* aBuilder,
     LayerProperties::ClearInvalidations(root);
   }
 
+  bool shouldInvalidate = layerManager->NeedsWidgetInvalidation();
   if (view) {
     if (props) {
       if (!invalid.IsEmpty()) {
@@ -1207,10 +1208,12 @@ void nsDisplayList::PaintForFrame(nsDisplayListBuilder* aBuilder,
                     presContext->DevPixelsToAppUnits(bounds.y),
                     presContext->DevPixelsToAppUnits(bounds.width),
                     presContext->DevPixelsToAppUnits(bounds.height));
-        view->GetViewManager()->InvalidateViewNoSuppression(view, rect);
+        if (shouldInvalidate) {
+          view->GetViewManager()->InvalidateViewNoSuppression(view, rect);
+        }
         presContext->NotifyInvalidation(bounds, 0);
       }
-    } else {
+    } else if (shouldInvalidate) {
       view->GetViewManager()->InvalidateView(view);
     }
   }

layout/base/nsPresShell.cpp

@@ -5489,8 +5489,6 @@ PresShell::Paint(nsView*        aViewToPaint,
     return;
   }
 
-  nsAutoNotifyDidPaint notifyDidPaint(this, aFlags);
-
   nsPresContext* presContext = GetPresContext();
   AUTO_LAYOUT_PHASE_ENTRY_POINT(presContext, Paint);
 
@@ -5500,6 +5498,13 @@ PresShell::Paint(nsView*        aViewToPaint,
   LayerManager* layerManager =
     aViewToPaint->GetWidget()->GetLayerManager(&isRetainingManager);
   NS_ASSERTION(layerManager, "Must be in paint event");
+  bool shouldInvalidate = layerManager->NeedsWidgetInvalidation();
+
+  uint32_t didPaintFlags = aFlags;
+  if (!shouldInvalidate) {
+    didPaintFlags |= PAINT_COMPOSITE;
+  }
+  nsAutoNotifyDidPaint notifyDidPaint(this, didPaintFlags);
 
   // Whether or not we should set first paint when painting is
   // suppressed is debatable. For now we'll do it because
@@ -5519,9 +5524,6 @@ PresShell::Paint(nsView*        aViewToPaint,
     // and b) below we don't want to clear NS_FRAME_UPDATE_LAYER_TREE,
     // that will cause us to forget to update the real layer manager!
     if (!(aFlags & PAINT_LAYERS)) {
-      if (layerManager->HasShadowManager() && Compositor::GetBackend() != LAYERS_BASIC) {
-        return;
-      }
       layerManager->BeginTransaction();
       if (layerManager->EndEmptyTransaction()) {
         return;
@@ -5556,10 +5558,12 @@ PresShell::Paint(nsView*        aViewToPaint,
                         presContext->DevPixelsToAppUnits(bounds.y),
                         presContext->DevPixelsToAppUnits(bounds.width),
                         presContext->DevPixelsToAppUnits(bounds.height));
-            aViewToPaint->GetViewManager()->InvalidateViewNoSuppression(aViewToPaint, rect);
+            if (shouldInvalidate) {
+              aViewToPaint->GetViewManager()->InvalidateViewNoSuppression(aViewToPaint, rect);
+            }
             presContext->NotifyInvalidation(bounds, 0);
           }
-        } else {
+        } else if (shouldInvalidate) {
           aViewToPaint->GetViewManager()->InvalidateView(aViewToPaint);
         }
 

layout/reftests/forms/input/range/reftest.list

@@ -21,8 +21,8 @@ default-preferences pref(dom.experimental_forms_range,true)
 == input-valueAsNumber-prop.html input-75pct-common-ref.html
 fails-if(B2G) == input-stepDown-unthemed.html input-75pct-unthemed-common-ref.html
 fails-if(B2G) == input-stepDown.html input-75pct-common-ref.html
-fails-if(B2G) == input-stepUp-unthemed.html input-75pct-unthemed-common-ref.html
-fails-if(B2G) == input-stepUp.html input-75pct-common-ref.html
+== input-stepUp-unthemed.html input-75pct-unthemed-common-ref.html
+== input-stepUp.html input-75pct-common-ref.html
 
 # 'direction' property:
 == input-range-direction-unthemed-1.html input-range-direction-unthemed-1-ref.html

view/src/nsViewManager.cpp

@@ -25,6 +25,7 @@
 #include "mozilla/Preferences.h"
 #include "nsContentUtils.h"
 #include "nsLayoutUtils.h"
+#include "mozilla/layers/Compositor.h"
 
 /**
    XXX TODO XXX
@@ -42,6 +43,8 @@
    we ask for a specific z-order, we don't assume that widget z-ordering actually works.
 */
 
+using namespace mozilla::layers;
+
 #define NSCOORD_NONE      INT32_MIN
 
 #undef DEBUG_MOUSE_LOCATION
@@ -330,8 +333,14 @@ void nsViewManager::Refresh(nsView *aView, const nsIntRegion& aRegion)
         printf("--COMPOSITE-- %p\n", mPresShell);
       }
 #endif
-      mPresShell->Paint(aView, damageRegion,
-                        nsIPresShell::PAINT_COMPOSITE);
+      uint32_t paintFlags = nsIPresShell::PAINT_COMPOSITE;
+      LayerManager *manager = widget->GetLayerManager();
+      if (!manager->NeedsWidgetInvalidation()) {
+        manager->FlushRendering();
+      } else {
+        mPresShell->Paint(aView, damageRegion,
+                          paintFlags);
+      }
 #ifdef MOZ_DUMP_PAINTING
       if (nsLayoutUtils::InvalidationDebuggingIsEnabled()) {
         printf("--ENDCOMPOSITE--\n");