Have GMs read the GrContext via a setter/getter rather than a global.

gm/bleed.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkBlurMask.h"
 #include "SkBlurMaskFilter.h"
 #include "SkCanvas.h"
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
-
-namespace skiagm {
-extern GrContext* GetGr();
-};
 #endif
 
 // Create a black&white checked texture with a 1-pixel red ring
 // around the outside edge
 static void make_red_ringed_bitmap(SkBitmap* result, int width, int height) {
     SkASSERT(0 == width % 2 && 0 == width % 2);
 
     result->setConfig(SkBitmap::kARGB_8888_Config, width, height);
     result->allocPixels();
     SkAutoLockPixels lock(*result);
@@ skipping 139 matching lines @@
         this->drawCase4(canvas, kCol0X, kRow3Y, SkCanvas::kNone_DrawBitmapRectFlag, false);
 
         // Then draw a column with no bleeding or tiling but with filtering
         this->drawCase1(canvas, kCol1X, kRow0Y, SkCanvas::kNone_DrawBitmapRectFlag, true);
         this->drawCase2(canvas, kCol1X, kRow1Y, SkCanvas::kNone_DrawBitmapRectFlag, true);
         this->drawCase3(canvas, kCol1X, kRow2Y, SkCanvas::kNone_DrawBitmapRectFlag, true);
         this->drawCase4(canvas, kCol1X, kRow3Y, SkCanvas::kNone_DrawBitmapRectFlag, true);
 
 
 #if SK_SUPPORT_GPU
-        GrContext* ctx = skiagm::GetGr();
+        GrContext* ctx = GM::GetGr(canvas);
         int oldMaxTextureSize = 0;
         if (NULL != ctx) {
             // shrink the max texture size so all our textures can be reasonably sized
             oldMaxTextureSize = ctx->getMaxTextureSize();
             ctx->setMaxTextureSizeOverride(kMaxTextureSize);
         }
 #endif
 
         // Then draw a column with no bleeding but with tiling and filtering
         this->drawCase1(canvas, kCol2X, kRow0Y, SkCanvas::kNone_DrawBitmapRectFlag, true);
@@ skipping 33 matching lines @@
     static const int kSmallTextureSize = 4;
     static const int kMaxTextureSize = 32;
 
     SkBitmap fBitmapSmall;
     SkBitmap fBitmapBig;
 
     typedef GM INHERITED;
 };
 
 DEF_GM( return new BleedGM(); )