Use IDCompositionSurface to implement DirectCompositionSurfaceWin.

gpu/GLES2/extensions/CHROMIUM/CHROMIUM_set_draw_rectangle.txt

+Name
+
+    CHROMIUM_set_draw_rectangle
+
+Name Strings
+
+    GL_CHROMIUM_set_draw_rectangle
+
+Version
+
+    Last Modified Date: Jan 23, 2017
+
+Dependencies
+
+    OpenGL ES 2.0 is required.
+
+Overview
+
+    This extension allows a client to indicate what area is going to be drawn to.
+
+Issues
+
+    None
+
+New Tokens
+
+    None
+
+New Procedures and Functions
+
+    The command
+
+        glSetDrawRectangleCHROMIUM (GLint x, GLint y, GLint width, GLint height);
+
+    indicates that the client will fill in the entire rectangle specified of
+    the default framebuffer. This command can only be specified once per swap.
+    If the extension is supported, this function must be called before any
+    drawing to the default framebuffer. The contents of the framebuffer are
+    undefined after this command and must be filled in completely before a
+    swap happens. Rendering outside this rectangle causes undefined behavior,
+    and the scissor test must be enabled when drawing.
+
+    For the first call to this, and the first call after a resize, the
+    rectangle must be equal to the size of the entire buffer.
+
+Errors
+
+    None.
+
+New State
+
+    None.