NX: code cleanup and bug fixes

-- BaseNavigtionBar: expose setKeyguardShowing public method
   and let StatusbarKeyguardView update us. Using this fixes a
   NxPulse bug in which if NXPulse was enabled and user paused
   music from Keyguard widget, the NxLogo would not invalidate
   when keyguard was dismissed

-- Remove unnecessary DelegateHelper code from NX by introducing
   a forceDisable public method in DelegatHelper

-- set onTouchListener in constructor instead of onInflate

Change-Id: I03c333a2cd72dcaf9acd7741e7030f9830c5277c