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/debug/GrGLCreateDebugInterface.cpp b/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
index 1cf9b53..b95b888 100644
--- a/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
+++ b/src/gpu/gl/debug/GrGLCreateDebugInterface.cpp
@@ -797,6 +797,7 @@
     interface->fColorMask = noOpGLColorMask;
     interface->fCompileShader = noOpGLCompileShader;
     interface->fCompressedTexImage2D = noOpGLCompressedTexImage2D;
+    interface->fCopyTexSubImage2D = noOpGLCopyTexSubImage2D;
     interface->fCreateProgram = debugGLCreateProgram;
     interface->fCreateShader = debugGLCreateShader;
     interface->fCullFace = noOpGLCullFace;