Merge changes I6aaf56f0,I11641791,I92c43548,I1afed9f5,If31a2ed7, ...

* changes:
  Remove unused method isKeyguardLocked
  Move clearing current method to controller
  Rename method clearing sessions appropriately
  Extract hiding status bar icon
  Reduce binding controller coupling to IMMS
  Factor out redundant getter calls
  Avoid unwarranted local variable
  Move setting curId and bindTime for symmetry
  Move and split removing window token
  Move adding fresh window token to controller
  Remove unwarranted local variable
  Move binding current method into the controller
  Extract binding current method logic
  Extract unbinding main IME connection
  Extract unbinding visible IME connection
  Move connectedness booleans into controller
  Split binding main and visible connection
  Move binding current method to controller
  Remove parameter from current input binding
  Move unbinding current method logic to controller
  Extract removing current window token
  Extract setting current method uid
  Inline getters and setters in binding controller
  Move IMMS service connection to the binding controller
  Add accessors for client-related members of IMMS
  Change IMMS not to implement ServiceConnection
  Move more encapsulated IMMS members
  Encapsulate more IMMS members
  Move visible connection state to ImeBindingController
  Encapsulate mVisibleBound in IMMS
  Encapsulate mVisibleConnection in IMMS
  Move encapsulated members to  binding controller
  Introduce InputMethodBindingController
  Avoid calculating the same time span twice
  Extract isSelectedMethodBound method
  Extract reusing current connection logic
  Extract part of the client switch logic
  Extract adding new window token in own method
  Extract updating binding intent
  Encapsulate IMMS members
  Make members final in IMMS where appropriate
  Use method references where available
  Remove unused member mIsLowRam