Add caps overrides to GMs

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 41 matching lines @@
     SkString fMsg;
     bool     fFatal;
 };
 
 struct Src {
     // All Srcs must be thread safe.
     virtual ~Src() {}
     virtual Error SK_WARN_UNUSED_RESULT draw(SkCanvas*) const = 0;
     virtual SkISize size() const = 0;
     virtual Name name() const = 0;
+    virtual void modifyGrContextOptions(GrContextOptions* options) const {}
 };
 
 struct Sink {
     virtual ~Sink() {}
     // You may write to either the bitmap or stream.  If you write to log, we'll print that out.
     virtual Error SK_WARN_UNUSED_RESULT draw(const Src&, SkBitmap*, SkWStream*, SkString* log)
         const = 0;
     // Sinks in the same enclave (except kAnyThread_Enclave) will run serially on the same thread.
     virtual int enclave() const = 0;
 
     // File extension for the content draw() outputs, e.g. "png", "pdf".
     virtual const char* fileExtension() const  = 0;
 };
 
 enum { kAnyThread_Enclave, kGPU_Enclave };
 static const int kNumEnclaves = kGPU_Enclave + 1;
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 class GMSrc : public Src {
 public:
     explicit GMSrc(skiagm::GMRegistry::Factory);
 
     Error draw(SkCanvas*) const override;
     SkISize size() const override;
     Name name() const override;
+    void modifyGrContextOptions(GrContextOptions* options) const override;
+
 private:
     skiagm::GMRegistry::Factory fFactory;
 };
 
 class CodecSrc : public Src {
 public:
     enum Mode {
         kNormal_Mode,
         kScanline_Mode,
     };
@@ skipping 182 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