DeviceKeyHandler: Increase handler priority

Allow DeviceKeyHandler to have higher priority when handling user keystrokes.

Patchset 2: Update commit message
Patchset 3: Rebased
Patchset 4: Fixed needed ref
Patchset 5: Rebased

Needed by http://review.cyanogenmod.org/#/c/35064

Change-Id: I60871052aaae0af7d864113f00dbdf9ba5200f2e
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Email force close when pressing back key after selecting characters

Email and Browser will be forced closed after selecting a text
and then press the back key, tilting the screen or trying to
share or copy the text. This is because a previouse fix
is using a part of the code that Google has removed.
Fix: clearSelection will now use its own EventHub id,
CLEAR_SELECT_TEXT.

This part describes the previous fix.
Marking a text on the web page and then press copy works,
but trying to mark the same text again does not work.
The reason for this is that the selection never gets
cleared in webkit.
The fix, calling cleaSelection in the onDestroyActionMode.
Also added clearSelection when getting an
onConfigurationChange.

FIX=DMS01503793

Change-Id: I5e5673bac4efb3d28e9fc613da4bf636f8ab3c39