use special-image for imagefilters and save/restore layer

src/image/SkImage_Base.h

Index: src/image/SkImage_Base.h
diff --git a/src/image/SkImage_Base.h b/src/image/SkImage_Base.h
index c01d9af63528efb18900ad0fa9a3bd55af3bdda1..fd52a55de1c2fe49a2c1b6d6c105b775c0921985 100644
--- a/src/image/SkImage_Base.h
+++ b/src/image/SkImage_Base.h
@@ -67,6 +67,11 @@ public:
         return this->getROPixels(bitmap, kAllow_CachingHint);
     }
 
+    virtual bool canBeImageFiltered() const {

[robertphillips, 2016/07/18 17:01:58]

Make this live ?

[reed1, 2016/07/18 22:06:07]

Done.

+        // bitmap.info().colorType() == kN32_SkColorType && !bitmap.info().gammaCloseToSRGB()
+        return true;
+    }
+
     // Call when this image is part of the key to a resourcecache entry. This allows the cache
     // to know automatically those entries can be purged when this SkImage deleted.
     void notifyAddedToCache() const {