Optionally pass rendertarget to getTestTarget

include/gpu/GrContext.h

Index: include/gpu/GrContext.h
diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 098fdd2fe9c2757c4645d885aac9f54e3f1c318a..7621f8b8265b158cfda2b877bd447aab3fdbd064 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -328,7 +328,7 @@ public:
     GrResourceCache* getResourceCache() { return fResourceCache; }
 
     // Called by tests that draw directly to the context via GrDrawTarget
-    void getTestTarget(GrTestTarget*);
+    void getTestTarget(GrTestTarget*, GrRenderTarget* rt);
 
     /** Prints cache stats to the string if GR_CACHE_STATS == 1. */
     void dumpCacheStats(SkString*) const;