[poc] redecode

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

Index: third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
index 75d52860e94d9a1014d4770d59a0fe07351fc066..b45eeb72d9511a6f95fd480855ca16e9cc9d2e57 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
@@ -63,6 +63,7 @@
 #include "platform/geometry/TransformState.h"
 #include "platform/graphics/BitmapImage.h"
 #include "platform/graphics/GraphicsContext.h"
+#include "platform/graphics/GraphicsScreen.h"
 #include "platform/graphics/paint/ClipDisplayItem.h"
 #include "platform/graphics/paint/CullRect.h"
 #include "platform/graphics/paint/PaintController.h"
@@ -1921,6 +1922,8 @@ void CompositedLayerMapping::updateImageContents()
     if (!image)
         return;
 
+    int64_t previousId = setCurrentScreenId(reinterpret_cast<int64_t>(layoutObject()->frame()->page()));
+
     // This is a no-op if the layer doesn't have an inner layer for the image.
     m_graphicsLayer->setContentsToImage(image, imageLayoutObject->shouldRespectImageOrientation());
 
@@ -1933,6 +1936,8 @@ void CompositedLayerMapping::updateImageContents()
     // the image. So we have to kick the animation each time; this has the downside that the
     // image will keep animating, even if its layer is not visible.
     image->startAnimation();
+
+    setCurrentScreenId(previousId);
 }
 
 FloatPoint3D CompositedLayerMapping::computeTransformOrigin(const IntRect& borderBox) const
@@ -2321,6 +2326,12 @@ void CompositedLayerMapping::paintContents(const GraphicsLayer* graphicsLayer, G
 {
     // https://code.google.com/p/chromium/issues/detail?id=343772
     DisableCompositingQueryAsserts disabler;
+
+    int64_t previousId = setCurrentScreenId(reinterpret_cast<int64_t>(layoutObject()->frame()->page()));
+
+    // fprintf(stderr, "CompositedLayerMapping::paintContents begins page %ld\n", (long int) currentScreenId());
+    // fflush(stderr);
+
 #if ENABLE(ASSERT)
     // FIXME: once the state machine is ready, this can be removed and we can refer to that instead.
     if (Page* page = layoutObject()->frame()->page())
@@ -2376,11 +2387,18 @@ void CompositedLayerMapping::paintContents(const GraphicsLayer* graphicsLayer, G
         ScrollableAreaPainter(*m_owningLayer.scrollableArea()).paintScrollCorner(&context, -scrollCornerAndResizerLocation, cullRect);
         ScrollableAreaPainter(*m_owningLayer.scrollableArea()).paintResizer(&context, -scrollCornerAndResizerLocation, cullRect);
     }
+
     InspectorInstrumentation::didPaint(m_owningLayer.layoutObject(), graphicsLayer, &context, LayoutRect(interestRect));
+
 #if ENABLE(ASSERT)
     if (Page* page = layoutObject()->frame()->page())
         page->setIsPainting(false);
 #endif
+
+    // fprintf(stderr, "CompositedLayerMapping::paintContents ends page %ld\n", (long int) currentScreenId());
+    // fflush(stderr);
+
+    setCurrentScreenId(previousId);
 }
 
 bool CompositedLayerMapping::isTrackingPaintInvalidations() const