One signature for creating unit tests that run on premade GrContexts

tests/ImageIsOpaqueTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTypes.h"
 #include "Test.h"
 
@@ skipping 48 matching lines @@
     auto surfaceTransparent(SkSurface::MakeRaster(infoTransparent));
     check_isopaque(reporter, surfaceTransparent, false);
 
     SkImageInfo infoOpaque = SkImageInfo::MakeN32(5, 5, kOpaque_SkAlphaType);
     auto surfaceOpaque(SkSurface::MakeRaster(infoOpaque));
     check_isopaque(reporter, surfaceOpaque, true);
 }
 
 #if SK_SUPPORT_GPU
 
-DEF_GPUTEST_FOR_RENDERING_CONTEXTS(ImageIsOpaqueTest_Gpu, reporter, context) {
+DEF_GPUTEST_FOR_RENDERING_CONTEXTS(ImageIsOpaqueTest_Gpu, reporter, ctxInfo) {
+    GrContext* context = ctxInfo.fGrContext;
     SkImageInfo infoTransparent = SkImageInfo::MakeN32Premul(5, 5);
     auto surfaceTransparent(SkSurface::MakeRenderTarget(context, SkBudgeted::kNo, infoTransparent));
     check_isopaque(reporter, surfaceTransparent, false);
 
     SkImageInfo infoOpaque = SkImageInfo::MakeN32(5, 5, kOpaque_SkAlphaType);
     auto surfaceOpaque(SkSurface::MakeRenderTarget(context,SkBudgeted::kNo, infoOpaque));
 
     check_isopaque(reporter, surfaceOpaque, true);
 }
 
 #endif