ResourceManager11: Store resource sizes 64-bit. This prevents possible size count overflow when in 32-bit mode with a lot of very large resources. Issue originally reported via Mozilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1412554 BUG=angleproject:2234 Change-Id: Idacfda98356c13bf22bc493ef7aa2bff1a287f97 Reviewed-on: https://chromium-review.googlesource.com/769749 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>