Add glCopyTexSubImage2D to GrGLInterface

Author: bsalomon@google.com

Reviewed By: robertphillips@google.com

Review URL: https://chromiumcodereview.appspot.com/13941006

git-svn-id: http://skia.googlecode.com/svn/trunk@8634 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/gl/GrGLInterface.cpp b/src/gpu/gl/GrGLInterface.cpp
index 0c6bd86..89912a0 100644
--- a/src/gpu/gl/GrGLInterface.cpp
+++ b/src/gpu/gl/GrGLInterface.cpp
@@ -59,6 +59,9 @@
         NULL == fClearStencil ||
         NULL == fColorMask ||
         NULL == fCompileShader ||
+#if 0  //  FIXME: Remove this once Chromium is updated to provide this function
+        NULL == fCopyTexSubImage2D ||
+#endif
         NULL == fCreateProgram ||
         NULL == fCreateShader ||
         NULL == fCullFace ||