GitLab

Use InstrumentationRegistry to get actual target context in the two
service test cases. Andr remove BaseITR, BaseChromiumITR, and ChromeITR

Bug: 807251
Change-Id: I9d945ce7c2ce264f84f10124af6b399cba690eef
Reviewed-on: https://chromium-review.googlesource.com/894125Reviewed-by: Tommy Nyquist <nyquist@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: Yoland Yan <yolandyan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533165}