Just pass the draw context to paint conversion

include/gpu/GrDrawContext.h

Index: include/gpu/GrDrawContext.h
diff --git a/include/gpu/GrDrawContext.h b/include/gpu/GrDrawContext.h
index b8ecca051e189a9455d76f1a175ed80052bbc860..3cc57b5365a64fd43e739a6f0887dda498dd7288 100644
--- a/include/gpu/GrDrawContext.h
+++ b/include/gpu/GrDrawContext.h
@@ -269,6 +269,10 @@ public:
     GrPixelConfig config() const { return fRenderTarget->config(); }
     int numColorSamples() const { return fRenderTarget->numColorSamples(); }
     bool isGammaCorrect() const { return fSurfaceProps.isGammaCorrect(); }
+    SkSourceGammaTreatment sourceGammaTreatment() const {
+        return this->isGammaCorrect() ? SkSourceGammaTreatment::kRespect
+                                      : SkSourceGammaTreatment::kIgnore;
+    }
     const SkSurfaceProps& surfaceProps() const { return fSurfaceProps; }
     SkColorSpace* getColorSpace() const { return fColorSpace.get(); }