First-run UI is enabled by default.

UI could be disabled by --disable-first-run-ui flag.
Suppresed loading of "Tips & Tricks" app in case when first-run UI is enabled.

BUG=269286
TBR=finnur
for extension_constants.*

Review URL: https://codereview.chromium.org/85293002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237057 0039d316-1c4b-4281-b951-d872f2087c98
SyncFS: Rename RemoveTrackerIgnoringSiblings


BUG=240165
TEST=n/a

Review URL: https://codereview.chromium.org/85363002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237058 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237057
SVN changes up to revision 237058