Sample for GPU memory dumping using new SkTraceMemoryDump.

include/gpu/GrContext.h

Index: include/gpu/GrContext.h
diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 50d101cf32f7227885499a06b35015278fdc3270..157fac8bc869a76e35d3c25afba3a689bc5bc304 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -42,6 +42,7 @@ class GrTextureParams;
 class GrVertexBuffer;
 class GrStrokeInfo;
 class GrSoftwarePathRenderer;
+class SkTraceMemoryDump;
 
 class SK_API GrContext : public SkRefCnt {
 public:
@@ -356,6 +357,9 @@ public:
         this is for testing only */
     void setTextBlobCacheLimit_ForTesting(size_t bytes);
 
+    /** Enumerates all cached resources and dumps their memory to traceMemoryDump. */
+    void onMemoryDump(SkTraceMemoryDump* traceMemoryDump) const;
+
 private:
     GrGpu*                          fGpu;
     const GrCaps*                   fCaps;