Update logic for interruptive notifications

- Only count visual changes for non-foreground service notifications,
because users consider the notification to be one 'session'
- Don't count every remoteviews update, but those where the layoutid
or sequence number has changed.

Bug: 78643290
Test: runtest systemui-notification
Change-Id: I49483d26ebe63329ef2d6d3f10dd730c310fcf2a