Support B8G8R8A8_UNORM_SRGB as D3D11 texture format Support B8G8R8A8_UNORM_SRGB as D3D11 texture format. BUG=angleproject:2172 Change-Id: I2f15a55123601735d7fc6caa40bb056243a91b44 Reviewed-on: https://chromium-review.googlesource.com/758600 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org>