Rename hideCurrentInputMethod() and pass a display ID

This is a mechanical renaming to clarify that this request would hide
all the input methods if there happened to be multiple input methods
running and shown.

Whether such a behavior is indeed valid or something that needs to be
updated will be discussed in bug 308479256.

Flag: NONE
Bug: 305829876
Bug: 308479256
Test: atest WmTests && atest FrameworksServicesTests
Change-Id: I464390927a9bea86769e11a6f97f1d4796991d77