Fix WebGPU context initialization

The WebGPU context was not properly created and initialized with the
SharedMemoryLimits.

Bug: 877147
Change-Id: I204fc041b914badadfc1c4c82530c14c0eda7059
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1521231
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#640596}
1 file changed