Theme special volumeup+down volume panel

When you press vol up + vol down button it brings up a
different volume panel which was not getting themed because
it lacked the ui context.

Change-Id: I416b8920160c0ab263fd426a6e6491d1f877a905
Themes: PhoneWindowManager UI context on demand

Creating the UI context in init causes some elements
like the power menu to not theme correctly. This solution follows
the same pattern as VolumePanel.

Change-Id: I5c12f9a3bc8f5fe8d96ef2775b840926a6c35e28

Conflicts:
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java