Framework: AOSP Fix - starting window memory leak

If starting window is added to arrays like mViews in
WindowManagerImpl.java, but not accepted by WindowManagerService,
we leak starting windows. To avoid leaking, remove the view
from WindowManager.

Change-Id: I4d98b883e9dfaf5e71bdece385643ba1b59b2633
Speed up notification pullup & pulldown

based on an idea by Mr.Nigma @xda:
http://forum.xda-developers.com/showthread.php?t=2267307

Change-Id: I61213058b5cedddf90e974713af05c038e3af039
Add method to PowerManager that allows querying the lowest possible
brightness.

Used by the auto-brightness adjustment to adjust the sliders.
Fix incorrect FloatMath documentation.

Change-Id: I30bbe500e634b73f3456ccc797106ad261fd0ce7
Process all display events in order

Display events in each batch received from IPC were being processed in
reverse order, and stopped after the first vsync event (latest
chronologically) was handled. This makes perfect sense for vsync
events, but is broken for hotplug events.

Now we process them all in order, handling all except vsync as we see
them. For vsync events, only the last is reported.

Bug: 7491120
Change-Id: I448d139d21dc27128d75ca1d661de666fff51bcb