In D3D11, check for 16-bit texture support and use if possible BUG=angleproject:1002 Change-Id: I36a5ee774b38e9865b2eb6c6789afd316c4eff16 Reviewed-on: https://chromium-review.googlesource.com/272061 Reviewed-by: Geoff Lang <geofflang@chromium.org> Tested-by: Austin Kinross <aukinros@microsoft.com>