Prevent UMA double counting in DeferredClientWrapper

This cl stores a flag whenever full browser is requested and UMA is
recorded so the UMA is only recorded once.

Change-Id: I22e620ac39933b463ec37933fb888526f372f1f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1628903
Auto-Submit: Mohamed Heikal <mheikal@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Commit-Queue: Mohamed Heikal <mheikal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663283}
2 files changed