This will be needed in the future when integer texture wrap mode support
will be added by sampling integer textures through FLOAT/UNORM/SNORM
SRVs.

The bit count needs to be passed for 8-, 10- and 16-bit textures. 32-bit
integer textures are the ones left over. Only passing the bit counts for
the absolute minimum number of formats avoids unnecessary driver constant
buffer updates.

BUG=angleproject:1244
BUG=angleproject:1095
TEST=angle_end2end_tests

Change-Id: I28a84588842b2eb9a1661454437d21c22ce794b7
Reviewed-on: https://chromium-review.googlesource.com/326944Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>