This CL enables the build/header_guard lint check. The existing headers
which failed the check were updated, missing headers added. An exclusion
file for the generator templates was added as well.
Bug: dawn:1339
Change-Id: If572e460179ad501293d5d6cf01e0ea900daa979
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/86207
Reviewed-by: Ben Clayton <bclayton@google.com>
Auto-Submit: Dan Sinclair <dsinclair@chromium.org>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
479dc6b7eb