Do not launch floating window when on default launcher

We only do this when user is on the default launcher
because if the user was on a non-default launcher,
he/she must have been there for some purpose and we
do not want to throw him/her back to the default
launcher incase he/she exits the app with HOME button.
Launch Heads Up in floating window [1/2]
    AICP'fied.
    To make floating window to work for Hover and Heads Up, notificationhelper
    interface is modified to include a third parameter to indicate whether it's
    called from hover or not.

    To make Heads_Up floating notification work separate from Hover,
    a third parameter is added to the notificationhelper to indicate whether
    we are called from Hover.java. This changes the call.

    PS2-3: Fix authorship
    PS5: separate hover change.
    PS6: change commit message.
    PS7: Merge with Hover change, fix setting preference and code cleanup.
         To make settings work, don't use Boolean with CM CheckBox preference
    PS8: autorship

    Original ChangeId: I530c3d9473e8b0600db047ce2137ee3d44592111

Conflicts:
	core/java/android/provider/Settings.java