Use skia::RefPtr to avoid having to manually refcount GraphicsContextState::m_looper.

Source/core/platform/graphics/GraphicsContext.h

Index: Source/core/platform/graphics/GraphicsContext.h
diff --git a/Source/core/platform/graphics/GraphicsContext.h b/Source/core/platform/graphics/GraphicsContext.h
index 11d16d2d5eb4512f23bcce79116bb33738a59c34..0dc1fc52d60e4db81e6523296257278c041fec1b 100644
--- a/Source/core/platform/graphics/GraphicsContext.h
+++ b/Source/core/platform/graphics/GraphicsContext.h
@@ -38,9 +38,10 @@
 #include "core/platform/graphics/ImageBuffer.h"
 #include "core/platform/graphics/ImageOrientation.h"
 #include "core/platform/graphics/skia/OpaqueRegionSkia.h"
-
-#include <wtf/Noncopyable.h>
-#include <wtf/PassOwnPtr.h>
+#include "wtf/FastAllocBase.h"
+#include "wtf/Forward.h"
+#include "wtf/Noncopyable.h"
+#include "wtf/PassOwnPtr.h"
 
 class SkBitmap;
 class SkDevice;
@@ -127,7 +128,7 @@ public:
     void setFillGradient(PassRefPtr<Gradient>);
     Gradient* fillGradient() const { return m_state->m_fillGradient.get(); }
 
-    SkDrawLooper* drawLooper() const { return m_state->m_looper; }
+    SkDrawLooper* drawLooper() const { return m_state->m_looper.get(); }
     SkColor effectiveStrokeColor() const { return m_state->applyAlpha(m_state->m_strokeData.color().rgb()); }
 
     int getNormalizedAlpha() const;
@@ -388,8 +389,6 @@ private:
         return value;
     }
 
-    void setDrawLooper(SkDrawLooper* looper) { SkRefCnt_SafeAssign(m_state->m_looper, looper); }
-
     // Sets up the common flags on a paint for antialiasing, effects, etc.
     // This is implicitly called by setupPaintFill and setupPaintStroke, but
     // you may wish to call it directly sometimes if you don't want that other