Enable stencil clipping in mixed sampled render targets

src/gpu/gl/GrGLGpu.h

Index: src/gpu/gl/GrGLGpu.h
diff --git a/src/gpu/gl/GrGLGpu.h b/src/gpu/gl/GrGLGpu.h
index 833f1ff7ec0356adeae9e6ffe1e7f9fd8a7b5f59..70df2399bae6f67a7d956bf080d9cc2599405186 100644
--- a/src/gpu/gl/GrGLGpu.h
+++ b/src/gpu/gl/GrGLGpu.h
@@ -256,12 +256,16 @@ private:
     // ensures that such operations don't negatively interact with tracking bound textures.
     void setScratchTextureUnit();
 
+    // colocates all samples at pixel center for render target, if MSAA.
+    // allows drawing coverage based AA shapes in MSAA mode.
+    void setCenteredSampleLocations(GrRenderTarget* rt, bool useCenteredSampleLocations);
+
     // bounds is region that may be modified and therefore has to be resolved.
     // nullptr means whole target. Can be an empty rect.
     void flushRenderTarget(GrGLRenderTarget*, const SkIRect* bounds);
 
     void flushStencil(const GrStencilSettings&);
-    void flushHWAAState(GrRenderTarget* rt, bool useHWAA);
+    void flushHWAAState(GrRenderTarget* rt, bool useHWAA, bool stencilEnabled);
 
     bool configToGLFormats(GrPixelConfig config,
                            bool getSizedInternal,