Cleanup: Go with SkDebugf instead of GrPrintf.

src/gpu/gl/GrGLExtensions.cpp

Index: src/gpu/gl/GrGLExtensions.cpp
diff --git a/src/gpu/gl/GrGLExtensions.cpp b/src/gpu/gl/GrGLExtensions.cpp
index 53013df64da1e4974fb073f4e66d6016ff793e3f..5ccb3393d40f45b27e2890f75b4cbcd03073dad8 100644
--- a/src/gpu/gl/GrGLExtensions.cpp
+++ b/src/gpu/gl/GrGLExtensions.cpp
@@ -138,6 +138,6 @@ void GrGLExtensions::print(const char* sep) const {
     }
     int cnt = fStrings->count();
     for (int i = 0; i < cnt; ++i) {
-        GrPrintf("%s%s", (*fStrings)[i].c_str(), (i < cnt - 1) ? sep : "");
+        SkDebugf("%s%s", (*fStrings)[i].c_str(), (i < cnt - 1) ? sep : "");
     }
 }