Cleanup: Go with SkDebugf instead of GrPrintf.

Since GrPrintf is just defined to SkDebugf, we can go with the later
directly.

BUG=None
TEST=None
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/695663003
diff --git a/src/gpu/GrBitmapTextContext.cpp b/src/gpu/GrBitmapTextContext.cpp
index c540dfd..a45aeae 100755
--- a/src/gpu/GrBitmapTextContext.cpp
+++ b/src/gpu/GrBitmapTextContext.cpp
@@ -597,7 +597,7 @@
                 if (kOne_GrBlendCoeff != fPaint.getSrcBlendCoeff() ||
                     kISA_GrBlendCoeff != fPaint.getDstBlendCoeff() ||
                     fPaint.numColorStages()) {
-                    GrPrintf("LCD Text will not draw correctly.\n");
+                    SkDebugf("LCD Text will not draw correctly.\n");
                 }
                 SkASSERT(!drawState->hasColorVertexAttribute());
                 // We don't use the GrPaint's color in this case because it's been premultiplied by