Add ifdef to not use function pointer that we don't have yet on Chromium??

R=bsalomon@google.com, robertphillips@google.com

Author: krajcevski@google.com

Review URL: https://codereview.chromium.org/326423003
diff --git a/src/gpu/gl/GrGLInterface.cpp b/src/gpu/gl/GrGLInterface.cpp
index 5062d92..b81d9ce 100644
--- a/src/gpu/gl/GrGLInterface.cpp
+++ b/src/gpu/gl/GrGLInterface.cpp
@@ -357,8 +357,11 @@
     if (kGL_GrGLStandard != fStandard ||
         (glVer >= GR_GL_VER(1,3)) ||
         fExtensions.has("GL_ARB_texture_compression")) {
-        if (NULL == fFunctions.fCompressedTexImage2D ||
-            NULL == fFunctions.fCompressedTexSubImage2D) {
+        if (NULL == fFunctions.fCompressedTexImage2D
+#if 0
+            || NULL == fFunctions.fCompressedTexSubImage2D
+#endif
+            ) {
             RETURN_FALSE_INTERFACE
         }
     }