Extract subpixel offsets from composited layer transforms when possible.

third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp

Index: third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp b/third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp
index 000a0c285e4211aa0adab7f7db558ebcdc01e0cc..73ef64054c301fdf6765a2ac59433a56acf5cd29 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp
@@ -96,6 +96,8 @@ PaintLayerPainter::PaintResult PaintLayerPainter::paintLayer(GraphicsContext& co
     if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled() && m_paintLayer.paintsWithTransform(paintingInfo.getGlobalPaintFlags()) && !(paintFlags & PaintLayerAppliedTransform))
         return paintLayerWithTransform(context, paintingInfo, paintFlags);
 
+
+
     return paintLayerContentsAndReflection(context, paintingInfo, paintFlags);
 }
 
@@ -522,6 +524,7 @@ PaintLayerPainter::PaintResult PaintLayerPainter::paintFragmentByApplyingTransfo
     TransformationMatrix transform(m_paintLayer.renderableTransform(paintingInfo.getGlobalPaintFlags()));
     IntPoint roundedDelta = roundedIntPoint(delta);
     transform.translateRight(roundedDelta.x(), roundedDelta.y());
+    LOG(ERROR) << "PaintLayerPainter::paintFragmentByApplyingTransform: delta x=" << roundedDelta.x() << ", y=" << roundedDelta.y();
     LayoutSize adjustedSubPixelAccumulation = paintingInfo.subPixelAccumulation + (delta - roundedDelta);
 
     // TODO(jbroman): Put the real transform origin here, instead of using a