Cleanup: Go with SkDebugf instead of GrPrintf.

src/gpu/GrDrawState.h

Index: src/gpu/GrDrawState.h
diff --git a/src/gpu/GrDrawState.h b/src/gpu/GrDrawState.h
index 036c4a517238d0b5d172d07f876e55c48beeff91..39c91027914138a8e6f2ca4a50b0ec5ad7004ce8 100644
--- a/src/gpu/GrDrawState.h
+++ b/src/gpu/GrDrawState.h
@@ -419,10 +419,10 @@ public:
         }
     #ifdef SK_DEBUG
         if (GrBlendCoeffRefsDst(dstCoeff)) {
-            GrPrintf("Unexpected dst blend coeff. Won't work correctly with coverage stages.\n");
+            SkDebugf("Unexpected dst blend coeff. Won't work correctly with coverage stages.\n");
         }
         if (GrBlendCoeffRefsSrc(srcCoeff)) {
-            GrPrintf("Unexpected src blend coeff. Won't work correctly with coverage stages.\n");
+            SkDebugf("Unexpected src blend coeff. Won't work correctly with coverage stages.\n");
         }
     #endif
     }