Revert of Make NVPR a GL context option instead of a GL context

dm/DMSrcSink.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 DMSrcSink_DEFINED
 #define DMSrcSink_DEFINED
 
@@ skipping 196 matching lines @@
 
     Error draw(const Src& src, SkBitmap*, SkWStream*, SkString*) const override;
     int enclave() const override { return kAnyThread_Enclave; }
     const char* fileExtension() const override { return ""; }
     SinkFlags flags() const override { return SinkFlags{ SinkFlags::kNull, SinkFlags::kDirect }; }
 };
 
 
 class GPUSink : public Sink {
 public:
-    GPUSink(GrContextFactory::GLContextType, GrGLStandard, int samples,
-            bool diText, bool threaded);
-    GPUSink(GrContextFactory::GLContextType, GrContextFactory::GLContextOptions,
-            GrGLStandard, int samples, bool diText, bool threaded);
+    GPUSink(GrContextFactory::GLContextType, GrGLStandard, int samples, bool diText, bool threaded);
 
     Error draw(const Src&, SkBitmap*, SkWStream*, SkString*) const override;
     int enclave() const override;
     const char* fileExtension() const override { return "png"; }
     SinkFlags flags() const override { return SinkFlags{ SinkFlags::kGPU, SinkFlags::kDirect }; }
 private:
-    GrContextFactory::GLContextType    fContextType;
-    GrContextFactory::GLContextOptions fContextOptions;
-    GrGLStandard                       fGpuAPI;
-    int                                fSampleCount;
-    bool                               fUseDIText;
-    bool                               fThreaded;
+    GrContextFactory::GLContextType fContextType;
+    GrGLStandard                    fGpuAPI;
+    int                             fSampleCount;
+    bool                            fUseDIText;
+    bool                            fThreaded;
 };
 
 class PDFSink : public Sink {
 public:
     PDFSink(const char* rasterizer);
 
     Error draw(const Src&, SkBitmap*, SkWStream*, SkString*) const override;
     int enclave() const override { return kAnyThread_Enclave; }
     const char* fileExtension() const override { return "pdf"; }
     SinkFlags flags() const override { return SinkFlags{ SinkFlags::kVector, SinkFlags::kDirect }; }
@@ skipping 119 matching lines @@
 
 class ViaTwice : public Via {
 public:
     explicit ViaTwice(Sink* sink) : Via(sink) {}
     Error draw(const Src&, SkBitmap*, SkWStream*, SkString*) const override;
 };
 
 }  // namespace DM
 
 #endif//DMSrcSink_DEFINED