Fix GL extension printing on core profiles.

R=robertphillips@google.com

Review URL: https://codereview.chromium.org/14864002

git-svn-id: http://skia.googlecode.com/svn/trunk@8970 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/gl/GrGLExtensions.h b/include/gpu/gl/GrGLExtensions.h
index d0970a6..f4e950a 100644
--- a/include/gpu/gl/GrGLExtensions.h
+++ b/include/gpu/gl/GrGLExtensions.h
@@ -40,6 +40,8 @@
 
     void reset() { fStrings.reset(); }
 
+    void print(const char* sep = "\n") const;
+
 private:
     SkTArray<SkString> fStrings;
 };