aura: Touch state file after first browser is ready.

aura: Touch state file after first browser is ready.

This creates a chromeos::InitialBrowserWindowObserver class
for Aura that replicates some behavior for tests that's
currently performed by the X window manager: when the first
browser window is created,
/var/run/state/windowmanager/initial-chrome-window-mapped is
touched (the window manager actually writes the window's ID
to the file, but that doesn't make sense under Aura and
luckily doesn't appear to be depended on by any tests).

This fixes Chrome OS's security_ProfilePermissions.BWSI and
security_ProfilePermissions.login autotests, which otherwise
time out when run against an Aura build.

I'm also moving existing X-window-manager-related files that
are currently in the chromeos/ directory to
chromeos/legacy_window_manager/.

BUG=chromium-os:22974, chromium-os:22896
TEST=manual: observed that tests no longer time out

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=110508

[DaveMoore, 2011-11-16 23:33:53]

lgtm

[commit-bot: I haz the power, 2011-11-16 23:49:07]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/derat@chromium.org/8539051/4001

[commit-bot: I haz the power, 2011-11-16 23:49:15]

Can't apply patch for file
chrome/browser/chromeos/chrome_browser_main_chromeos.cc.
While running patch -p1 --forward --force;
patching file chrome/browser/chromeos/chrome_browser_main_chromeos.cc
Hunk #2 FAILED at 170.
1 out of 2 hunks FAILED -- saving rejects to file
chrome/browser/chromeos/chrome_browser_main_chromeos.cc.rej