Replace uses of GR_DEBUG by SK_DEBUG.

gm/gmmain.cpp

Index: gm/gmmain.cpp
diff --git a/gm/gmmain.cpp b/gm/gmmain.cpp
index 773e1e769c72811cf458aac59278b3cd1a3d2c04..f6a8c1bd7f5a5ade76519ff4fccaacf49c16254c 100644
--- a/gm/gmmain.cpp
+++ b/gm/gmmain.cpp
@@ -1247,12 +1247,12 @@ static const ConfigData gRec[] = {
     { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kNative_GLContextType,  4, kRW_ConfigFlag,    "msaa4",        false},
     /* The gpudebug context does not generate meaningful images, so don't record
      * the images it generates!  We only run it to look for asserts. */
-    { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kDebug_GLContextType,   0, kNone_ConfigFlag,  "gpudebug",     GR_DEBUG},
+    { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kDebug_GLContextType,   0, kNone_ConfigFlag,  "gpudebug",     SK_DEBUG},
     /* The gpunull context does the least amount of work possible and doesn't
        generate meaninful images, so don't record them!. It can be run to
        isolate the CPU-side processing expense from the GPU-side.
       */
-    { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kNull_GLContextType,    0, kNone_ConfigFlag,  "gpunull",      GR_DEBUG},
+    { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kNull_GLContextType,    0, kNone_ConfigFlag,  "gpunull",      SK_DEBUG},
 #if SK_ANGLE
     { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kANGLE_GLContextType,   0, kRW_ConfigFlag,    "angle",        true },
     { SkBitmap::kARGB_8888_Config, kGPU_Backend,    GrContextFactory::kANGLE_GLContextType,  16, kRW_ConfigFlag,    "anglemsaa16",  true },