Annotate methods in IInputMethodManager with @RequiresPermission

This CL adds @RequiresPermission annotations to IInputMethodManager
binder methods.

Since @RequiresPermission is just a source-level annotation, there
should be no observable behavior change.

Bug: 237316307
Test: compile
Change-Id: Iea02937d19e0353725d1eb1c9553236c93a4a71d
1 file changed