Reduce over notification of topFocusedWindowChange

Registered remote inset controllers are being greatly over notified
through this API when there are no changes. This change will reduce this
notification to only occur when one (or both) of the parameters change.

Bug: 385355211
Test: manual, presubmit
Flag: NONE bugfix
Change-Id: I171dd2e7d81d86f9d5963609ecf2019a82193ab1