purge imagefilter cache so we can better track leaks

include/core/SkImageFilter.h

Index: include/core/SkImageFilter.h
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index dab46ae716b69ffb76f9adcf726342289ecda4cb..b7cc07ea9293f6292acc6b91d0e4ed252fad7b64 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -61,6 +61,7 @@ public:
         static Cache* Get();
         virtual bool get(const Key& key, SkBitmap* result, SkIPoint* offset) const = 0;
         virtual void set(const Key& key, const SkBitmap& result, const SkIPoint& offset) = 0;
+        virtual void purge() {}
     };
 
     class Context {
@@ -342,6 +343,9 @@ protected:
                                      const SkIRect& bounds) const;
 
 private:

[robertphillips, 2015/05/20 20:28:19]

// for PurgeCache call ?

+    friend class SkGraphics;
+    static void PurgeCache();
+
     bool usesSrcInput() const { return fUsesSrcInput; }
 
     typedef SkFlattenable INHERITED;