Save running SW instance info, including its SiteInstance, into the ProcessManager.
We can use this map to drop all the process references on shutdown, in order to
fix http://crbug.com/368570.
This starts to fix an assumption in the content layer that SiteInstances outlive
their RPHs so that process permissions can be controlled through the
SiteInstance instead of by process id. However, there's still work to do before
that's completely fixed.
This reverts https://codereview.chromium.org/
296053013/ and avoids the incorrect
down-cast that caused https://codereview.chromium.org/
292903002 to break the
Asan bot.
BUG=368570
Review URL: https://codereview.chromium.org/
294073009
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272490 0039d316-1c4b-4281-b951-d872f2087c98