GitLab

ShellExtensionLoaderTest associates a new TestingPrefServiceSimple with
the BrowserContext, but instead should associate the existing
PrefService created by ExtensionsTest.

Creating its own TestingPrefServiceSimple, besides being unnecessary,
leads to invalid casts of its PrefRegistrySimple to a
PrefRegistrySyncable (breaking the Linux CFI bots).

TBR=rdevlin.cronin@chromium.org

Bug: 820647
Change-Id: I2ae62a396622d034c8c5b04bbe9dabb529b5bd25
Reviewed-on: https://chromium-review.googlesource.com/957871Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Commit-Queue: Michael Giuffrida <michaelpg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542302}