Make filters use SkImage instead of SkBitmap

src/core/SkDeviceImageFilterProxy.h

Index: src/core/SkDeviceImageFilterProxy.h
diff --git a/src/core/SkDeviceImageFilterProxy.h b/src/core/SkDeviceImageFilterProxy.h
index 0ae686d877df4b81eb0b2c68bfe566a91d96af5c..4e74bfca2ce2b3bad3b717de37d141b0b69cb4d3 100644
--- a/src/core/SkDeviceImageFilterProxy.h
+++ b/src/core/SkDeviceImageFilterProxy.h
@@ -22,18 +22,18 @@ public:
                                                           props.pixelGeometry()))
     {}
 
-    SkBaseDevice* createDevice(int w, int h) SK_OVERRIDE {
+    SkSurface* createSurface(int w, int h) SK_OVERRIDE {
         SkBaseDevice::CreateInfo cinfo(SkImageInfo::MakeN32Premul(w, h),
                                        SkBaseDevice::kImageFilter_Usage,
                                        kUnknown_SkPixelGeometry);
-        return fDevice->onCreateCompatibleDevice(cinfo);
+        return fDevice->onCreateCompatibleSurface(cinfo);
     }
     bool canHandleImageFilter(const SkImageFilter* filter) SK_OVERRIDE {
         return fDevice->canHandleImageFilter(filter);
     }
-    virtual bool filterImage(const SkImageFilter* filter, const SkBitmap& src,
+    virtual bool filterImage(const SkImageFilter* filter, SkImage& src,
                              const SkImageFilter::Context& ctx,
-                             SkBitmap* result, SkIPoint* offset) SK_OVERRIDE {
+                             SkAutoTUnref<SkImage>& result, SkIPoint* offset) SK_OVERRIDE {
         return fDevice->filterImage(filter, src, ctx, result, offset);
     }