cmaa : Flip internally allocated framebuffer

MESA_framebuffer_flip_y needs the allocated framebuffer
to be setup to the same orientation.

BUG=964010
TEST=https://www.khronos.org/registry/webgl/sdk/tests/conformance/context/context-size-change.html?webglVersion=2

(cherry picked from commit e78b3019120dd19bcff7d853e89976e9be343146)

Change-Id: If7b7aaec176387e47c46c4f7337d686536375e8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1641666
Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Fritz Koenig <frkoenig@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#666113}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1660785
Cr-Commit-Position: refs/branch-heads/3809@{#327}
Cr-Branched-From: d82dec1a818f378c464ba307ddd9c92133eac355-refs/heads/master@{#665002}

• gpu/command_buffer/service/framebuffer_manager.cc[diff]
• gpu/command_buffer/service/framebuffer_manager.h[diff]
• gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc[diff]
• gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.h[diff]
• gpu/command_buffer/service/gles2_cmd_decoder.cc[diff]