media: Added UMA stats on how many devices can get shared textures

Log this in an UMA histogram to determine what proportion of frames
might actually benefit from zero-copy
(https://chromium-review.googlesource.com/c/chromium/src/+/4323337)

Bug: 1120900
Change-Id: Icb612e64e5ec5136ee5c60beb5891f99c2f57320
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4531789
Reviewed-by: Ilya Nikolaevskiy <ilnik@chromium.org>
Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Commit-Queue: Shuhai Peng <shuhai.peng@intel.com>
Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1146373}