Refactor DrawTarget and GPU to be independent

src/gpu/gl/GrGpuGL.h

Index: src/gpu/gl/GrGpuGL.h
diff --git a/src/gpu/gl/GrGpuGL.h b/src/gpu/gl/GrGpuGL.h
index 9a491906ba73b2ae427df0cdf69335031d7fb013..bba6400f468ee7cb40f90a14bc21af00dfc76dc9 100644
--- a/src/gpu/gl/GrGpuGL.h
+++ b/src/gpu/gl/GrGpuGL.h
@@ -153,7 +153,7 @@ private:
 
     virtual void onResolveRenderTarget(GrRenderTarget* target) SK_OVERRIDE;
 
-    virtual void onGpuDraw(const DrawInfo&) SK_OVERRIDE;
+    virtual void onGpuDraw(const GrDrawTarget::DrawInfo&) SK_OVERRIDE;
 
 
     virtual void clearStencil(GrRenderTarget*) SK_OVERRIDE;
@@ -171,7 +171,7 @@ private:
     // Sets up vertex attribute pointers and strides. On return indexOffsetInBytes gives the offset
     // an into the index buffer. It does not account for drawInfo.startIndex() but rather the start
     // index is relative to the returned offset.
-    void setupGeometry(const DrawInfo& info, size_t* indexOffsetInBytes);
+    void setupGeometry(const GrDrawTarget::DrawInfo& info, size_t* indexOffsetInBytes);
 
     // Subclasses should call this to flush the blend state.
     // The params should be the final coefficients to apply