Factor painting code for filters out of FilterEffectRenderer into FilterPainter.

Source/core/paint/LayerPainter.cpp

Index: Source/core/paint/LayerPainter.cpp
diff --git a/Source/core/paint/LayerPainter.cpp b/Source/core/paint/LayerPainter.cpp
index 1ca2e32ed7f073085436266a76309bb76974c354..db8f36832f689e4ad64d16192361933d3b6981b0 100644
--- a/Source/core/paint/LayerPainter.cpp
+++ b/Source/core/paint/LayerPainter.cpp
@@ -7,6 +7,7 @@
 
 #include "core/frame/Settings.h"
 #include "core/page/Page.h"
+#include "core/paint/FilterPainter.h"
 #include "core/rendering/ClipPathOperation.h"
 #include "core/rendering/FilterEffectRenderer.h"
 #include "core/rendering/PaintInfo.h"
@@ -276,6 +277,7 @@ void LayerPainter::paintLayerContents(GraphicsContext* context, const LayerPaint
 
     { // Begin block for the lifetime of any filter clip.
         OwnPtr<ClipRecorder> clipRecorder;
+        FilterPainter filterPainter(m_renderLayer);
         if (haveFilterEffect) {
             ASSERT(m_renderLayer.filterInfo());
 
@@ -301,7 +303,7 @@ void LayerPainter::paintLayerContents(GraphicsContext* context, const LayerPaint
             // Subsequent code should not clip to the dirty rect, since we've already
             // done it above, and doing it later will defeat the outsets.
             localPaintingInfo.clipToDirtyRect = false;
-            haveFilterEffect = m_renderLayer.filterRenderer()->beginFilterEffect(context, rootRelativeBounds);
+            haveFilterEffect = filterPainter.beginFilterEffect(context, rootRelativeBounds);
             if (!haveFilterEffect) {
                 // If the the filter failed to start, undo the clip immediately
                 clipRecorder.clear();
@@ -347,7 +349,7 @@ void LayerPainter::paintLayerContents(GraphicsContext* context, const LayerPaint
         if (haveFilterEffect) {
             // Apply the correct clipping (ie. overflow: hidden).
             // FIXME: It is incorrect to just clip to the damageRect here once multiple fragments are involved.
-            m_renderLayer.filterRenderer()->endFilterEffect(context);
+            filterPainter.endFilterEffect(context);

[mstensho (USE GERRIT), 2014/11/11 08:15:29]

Can't you just have ~FilterPainter() do this job, to achieve a half-RAII
experience? :)

You could store |context| as a member when calling beginFilterEffect().

         }
     } // Filter clip block