GitLab

Remove:
- ExtensionBrowserTest::installed_
- ExtensionBrowserTest::loaded_
- ExtensionBrowserTest::LaunchBrowserForAppInTab()
- ExtensionBrowserTest::InstallExtensionWithUI()
- ExtensionBrowserTest::WaitForExtensionLoadError()
- browser_test_util::LaunchBrowserForAppInTab()

None of these had active usage.

No functional changes; pure deletion.

Bug: None
Change-Id: I815af35198ebeb0b75139086060eedb48a0d8209
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1981067Reviewed-by: David Bertoni <dbertoni@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#727472}