Feature Level 9_3 doesn't support as many formats for Input Layouts
as 10_0+. On 9_3, we have to make sure that GL vertex attributes are
converted into formats that 9_3 supports.

Change-Id: I27b9a85a6eb21a37bd36e60bf011b83fce743fd0
Reviewed-on: https://chromium-review.googlesource.com/234523Tested-by: Austin Kinross <aukinros@microsoft.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>