Create new target to hold gpu test code, enable direct testing of GrEffects in GM.

R=robertphillips@google.com, jvanverth@google.com, egdaniel@google.com

Author: bsalomon@google.com

Review URL: https://chromiumcodereview.appspot.com/23352003

git-svn-id: http://skia.googlecode.com/svn/trunk/include@10866 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/GrContext.h b/gpu/GrContext.h
index ab38709..ae932bd 100644
--- a/gpu/GrContext.h
+++ b/gpu/GrContext.h
@@ -33,6 +33,7 @@
 class GrResourceEntry;
 class GrResourceCache;
 class GrStencilBuffer;
+class GrTestTarget;
 class GrTextureParams;
 class GrVertexBuffer;
 class GrVertexBufferAllocPool;
@@ -825,6 +826,9 @@
     GrDrawTarget* getTextTarget();
     const GrIndexBuffer* getQuadIndexBuffer() const;
 
+    // Called by tests that draw directly to the context via GrDrawTarget
+    void getTestTarget(GrTestTarget*);
+
     /**
      * Stencil buffers add themselves to the cache using addStencilBuffer. findStencilBuffer is
      * called to check the cache for a SB that matches an RT's criteria.