GitLab

Move all the code related to clearing browsing data to
IOSChromeBrowsingDataRemover after remarking that method
-removeIOSSpecificIncognitoBrowsingDataFromBrowserState:..
is unnecessary as -removeBrowsingDataFromBrowserState:...
clear exactly the same data is BrowserState is incognito.

Refactor some method clearing browsing data to accept a
closure (those that are asynchronous).

Bug: none
Change-Id: I7dfbb7040b87343fdd3df3b473a7d4c2046d4c46
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Reviewed-on: https://chromium-review.googlesource.com/919264
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537809}