Unregister Images, Plugins and Mouselock content settings on android
Images, plugins and mouselock content settings aren't used on Android, so
unregister them in ContentSettingsRegistry and handle places in shared code
where get access to these types.
Several places in shared code are if-defed out when they try to get access to
unregistered types. Some tests are also changed to use COOKIES instead of IMAGES
to make the tests more platform generic, if they are not testing images
specifically.
This is a follow up CL of
https://codereview.chromium.org/1991623005/.
BUG=
604632
TBR=
msramek@chromium.org
Committed:
https://crrev.com/e085f20530d930427a3efff3a2fd9aa2f94d61a9
Cr-Commit-Position: refs/heads/master@{#399634}