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/include/gpu/gl/GrGLFunctions.h b/include/gpu/gl/GrGLFunctions.h
index 037ebfd..1d96849 100644
--- a/include/gpu/gl/GrGLFunctions.h
+++ b/include/gpu/gl/GrGLFunctions.h
@@ -64,6 +64,7 @@
     typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLColorMaskProc)(GrGLboolean red, GrGLboolean green, GrGLboolean blue, GrGLboolean alpha);
     typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLCompileShaderProc)(GrGLuint shader);
     typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLCompressedTexImage2DProc)(GrGLenum target, GrGLint level, GrGLenum internalformat, GrGLsizei width, GrGLsizei height, GrGLint border, GrGLsizei imageSize, const GrGLvoid* data);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLCopyTexSubImage2DProc)(GrGLenum target, GrGLint level, GrGLint xoffset, GrGLint yoffset, GrGLint x, GrGLint y, GrGLsizei width, GrGLsizei height);
     typedef GrGLuint (GR_GL_FUNCTION_TYPE* GrGLCreateProgramProc)(void);
     typedef GrGLuint (GR_GL_FUNCTION_TYPE* GrGLCreateShaderProc)(GrGLenum type);
     typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLCullFaceProc)(GrGLenum mode);