frameworks/base: Add support for low resolution rendering

This change is a combination of following changes:

1) frameworks/base: Handle custom activityTrigger flags
    * Take necessary action needed for each vendor specific flag
    set as part of activityTrigger.
    * If the HW acceleration has to be enabled for a particular
    activity, populate the neccessary activityInfo flags.
    * If the resolution needs to be overridden for SurfaceView
    of a specific app, set the overrideRes to 1 in applicationInfo.
    Author: Raj Kamal<rkamal@codeaurora.org>
    Change-Id: Ic835ec1f2ebcc016542ace4050bfef5fb32f20a0

2) frameworks/base: Add support to render certain apps at lower
                    resolution.
    Add support to render certain apps at a resolution lower than the
    primary display device resolution. This would reduce the load on
    GPU and would help in saving power
    Author: Uday Kiran jandhyala<ukiran@codeaurora.org>
    Change-Id: I7004a145f3048aafbfb456451e08ea5ba229cfe9

3)  frameworks/base: Bail out early if Resolution override disabled

    There is a f/w bug that causes the resources to be not initialized
    leading to a crash in ResolutionOverride. This change bails out
    early before calling getResources(), if Resolution override is
    disabled. Also adds null checks for getResources() for cases where
    the feature is enabled.
    Author: Saurabh Shah<saurshah@codeaurora.org>
    Change-Id: I3fa362a153fb39d933b1aa17a5fac8affdd041d8

This change also moves out custom functionality related to
overriding resolution from SurfaceView, to a new class
ResolutionOverride.

Change-Id: Icabc17b9462a347c9c452cc53222ea7dcb6f336b