SystemUI: open settings panel if there are no notifications

If there are no notifications that belong to the current user, then automatically open the quick settings menu (like the two-finger open). It only ignores the ADB icon for now (which is pretty useless) but could be extended to ignore the usb mounting one or maybe another?

TODO: add Settings.System toggle to disable the option

Signed-off-by: Roman Birg <romanbirg@gmail.com>

Conflicts:

	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java

Change-Id: I9af55ac66cf4ee9fd6615cc19b30707b3ed33364
Quick settings pulldown

This is always enabled with a fixed 80% width trigger.
Allow custom density setting

Use system property persist.lcd_density to set custom density.  The custom
setting affects the entire UI.  It is independent of ro.sf.lcd_density and
has no effect on play store compatibility.

Code distilled from PA project via PAC project.

Conflicts:

	core/java/android/content/res/Resources.java

Change-Id: I8d26405d5d33bdf2890a0e9f67f113a4dc3e763b