Include EXT_window_rectangles API

include/gpu/gl/GrGLFunctions.h

Index: include/gpu/gl/GrGLFunctions.h
diff --git a/include/gpu/gl/GrGLFunctions.h b/include/gpu/gl/GrGLFunctions.h
index 7822eac81aabedabc770b3d27507b94aaf209188..4dff208a9b9a48c7bbf75d23b547813a900120ef 100644
--- a/include/gpu/gl/GrGLFunctions.h
+++ b/include/gpu/gl/GrGLFunctions.h
@@ -353,6 +353,9 @@ typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLPushDebugGroupProc)(GrGLenum source,
 typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLPopDebugGroupProc)();
 typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLObjectLabelProc)(GrGLenum identifier, GrGLuint name, GrGLsizei length, const GrGLchar *label);
 
+/** EXT_window_rectangles */
+typedef GrGLvoid (GR_GL_FUNCTION_TYPE* GrGLWindowRectanglesProc)(GrGLenum mode, GrGLsizei count, const GrGLint box[]);
+
 /** EGL functions */
 typedef const char* (GR_GL_FUNCTION_TYPE* GrEGLQueryStringProc)(GrEGLDisplay dpy, GrEGLint name);
 typedef GrEGLDisplay (GR_GL_FUNCTION_TYPE* GrEGLGetCurrentDisplayProc)();