Implement EXT_window_rectangles in command buffer

Spec: https://www.khronos.org/registry/OpenGL/extensions/EXT/EXT_window_rectangles.txt

Bug: 644265
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I3c4bae9cae8cf839fcf20103db1976e24e148000
Reviewed-on: https://chromium-review.googlesource.com/741866
Commit-Queue: Kai Ninomiya <[email protected]>
Reviewed-by: Antoine Labour <[email protected]>
Cr-Commit-Position: refs/heads/master@{#513884}
diff --git a/gpu/command_buffer/cmd_buffer_functions.txt b/gpu/command_buffer/cmd_buffer_functions.txt
index 87cbc39..4e65c80 100644
--- a/gpu/command_buffer/cmd_buffer_functions.txt
+++ b/gpu/command_buffer/cmd_buffer_functions.txt
@@ -387,3 +387,6 @@
 
 // Extension CHROMIUM_color_space_metadata
 GL_APICALL void         GL_APIENTRY glSetColorSpaceMetadataCHROMIUM (GLuint texture_id, GLColorSpace color_space);
+
+// Extension EXT_window_rectangles
+GL_APICALL void         GL_APIENTRY glWindowRectanglesEXT (GLenumWindowRectanglesMode mode, GLsizeiNotNegative count, const GLint* box);