Reduce observers in SystemUI: StatusBarIconView

Currently, for each status bar icon view there is a observer that
listens for changes of STATUS_BAR_NOTIF_COUNT. With one
notification usually having one or more status bar icons
you may end up easily with 10+ more observers for ~5 notifications.

With this commit the internal observer class becomes a singleton.
This means there is now only one observer for all status bar icons
and additional binder calls on new notification are avoided.

See "dumpsys content"

Change-Id: I8c11b165b34b87e7363a8e96524ea70fe6b28342
frameworks_base: SK Translations

Change-Id: I16d9aebb6819ca3fbcda417343c8d2d895117f42
core: NL translations

Change-Id: I3e3cc274105e55798a3fe1ece4f5f236019b75ae
AudioService: Remove STREAM_NOTIFICATION from ringer mode streams

Change-Id: Ie8d25743b27839fa2bd4e9ae5d3d0a49410ac5b4
JIRA: CYAN-344
Issue: https://jira.cyanogenmod.org/browse/CYAN-344
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_frameworks_base into myjb-next