Remove NetworkState dependency from GetCaptivePortalState

GetCaptivePortalState only uses NetworkState.path, so pass that directly
to avoid an unnecessary extra lookup + dependency in the UI code.

BUG=240237
R=pneubeck@chromium.org, ygorshenin@chromium.org

Review URL: https://codereview.chromium.org/179903003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253628 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253628
Always drop the First Run sentinel in the User Data directory.

Also:
  1) Don't RemoveSentinel on uninstall (also required to address issue 341049).
  2) Copy the legacy First Run sentinel to the new location on user-level installs.
  3) Reorder chrome_browser_main to put early return paths as early as possible + make sure first_run::CreateSentinelIfNeeded() comes AFTER any early return.
  4) Have all sentinel obtention code go through InstallUtil::GetSentinelFilePathForDist() (renamed from InstallUtil::GetSentinelFilePath() to highlight all affected paths -- which were already all system-level only paths, except for the self-destruct path which is no longer required and was removed along with --cancel-first-run).
  5) Introduce installer::switches::kTriggerActiveSetup to allow Chrome to tell setup.exe that it should trigger active setup if the system-level Chrome taking over will not undergo first run (rather than relying on setup to read the first run sentinel itself).

BUG=341049
TEST=
A:
1) Install+run old user-level chrome (goes through first run)
2) Close old chrome
3) Install new chrome and run it (ensure First Run beacon is migrated and no first run flow occurs)
4) Uninstall new chrome and make sure the Application folder is deleted despite the lingering First Run sentinel which is no longer actively removed on uninstall.

B: Self-destruct flow still works as intended (uninstalls user-level and launches system-level in first run or not, just like user-level should have launched)

Review URL: https://codereview.chromium.org/166853003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253630 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253630