Make IInputMethodManager to oneway (9/N)

Apply following methods to IVoidResultCallback to emulate
current behavior before we change them to one-way.

-. showInputMethodPickerFromClient
-. showInputMethodPickerFromSystem
-. showInputMethodAndSubtypeEnablerFromClient
-. reportActivityView

Bug: 163453493
Test: Manual test with keyboard
Test: atest CtsInputMethodTestCases
Test: atest CtsWindowManagerDeviceTestCases:ActivityViewTest
Change-Id: Id516fd1c961f43ac3e139c88d7ed004c188d458b