Revert behavior of DateUtils.formatElapsedTime

Change Ib3c1e1aad05827df646aa18645cce19dffb7551f fixes the inability
to display more that 2-digit hour values, but also changes the behavior
of <10 minutes display by zero-padding the minutes. This makes
the Chronometer widget look different, and breaks Holo CTS.

Fix it so that for values under 600 seconds, the minutes don't
get padded

Change-Id: I34eb7f22e728c55bf3313ed1987ac32969cd5ed0
QS: Don't assume observers are registered when dealing with changes

Not all uri activity has an associated content observer. Poking
the content://settings/system provider manually, for example,
would result in the following NPE:

AndroidRuntime: FATAL EXCEPTION: main
AndroidRuntime: java.lang.NullPointerException
AndroidRuntime:        at com.android.systemui.statusbar.phone.QuickSettingsController$QuickSettingsObserver.onChange(QuickSettingsController.java:354)
AndroidRuntime:        at android.database.ContentObserver$NotificationRunnable.run(ContentObserver.java:180)
AndroidRuntime:        at android.os.Handler.handleCallback(Handler.java:725)

Change-Id: I7034d261804aa972fe9020dd9b602348d249cb33
WebSettings: Move CM tag to the end of the user-agent

Append it at the end of everything to make it less obtrusive to
agent parsers, and append the CM device identifier so we can present
smarter choices when our sites are accessed.

Change-Id: I1e60d13be4cca9043e434a31bfc4fa08e01a12c0
Fix DateUtils.formatElapsedTime, again

Remove extraneous "hours" argument in the <10 minutes case

Change-Id: I5a5913d2e0744f5783f8422cddc30603c7bd703f
Merge remote-tracking branch 'upstream/cm-10.1' into cm-10.1-dev