Just pass the draw context to paint conversion

include/gpu/GrDrawContext.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrDrawContext_DEFINED
 #define GrDrawContext_DEFINED
 
@@ skipping 251 matching lines @@
     bool mustUseHWAA(const GrPaint& paint) const {
         return paint.isAntiAlias() && fRenderTarget->isUnifiedMultisampled();
     }
 
     const GrSurfaceDesc& desc() const { return fRenderTarget->desc(); }
     int width() const { return fRenderTarget->width(); }
     int height() const { return fRenderTarget->height(); }
     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(); }
 
     bool wasAbandoned() const;
 
     GrRenderTarget* accessRenderTarget() { return fRenderTarget.get(); }
 
     sk_sp<GrRenderTarget> renderTarget() { return fRenderTarget; }
 
     sk_sp<GrTexture> asTexture() { return sk_ref_sp(fRenderTarget->asTexture()); }
@@ skipping 80 matching lines @@
 
     sk_sp<SkColorSpace>               fColorSpace;
     SkSurfaceProps                    fSurfaceProps;
     GrAuditTrail*                     fAuditTrail;
 
     // In debug builds we guard against improper thread handling
     SkDEBUGCODE(mutable GrSingleOwner* fSingleOwner;)
 };
 
 #endif