Refactor AttachInfo.mGlobalSystemUiVisibility

Move it to ViewRootImpl and rename it: mDispatchedSystemUiVisibility
with default value 0 in the new insets mode instead of -1. Because
mCompatibleVisibilityInfo.globalVisibility will always be updated in the
new insets mode, we don't need the -1 value to detect the change from
non-zero value to zero dispatched from the server.

Bug: 118118435
Test: atest LayoutTests
Change-Id: I45064bdcdca37b9a2b30d82bb9d9c84e45732029