Add tappable elements insets types to WM Wrapper

This is to let the apps, such as launcher to be able to provide tappable
elements insets. This is necessary as the launcher may add task bar to
the system and it should behave as a tappable elements insets source

Test: go/wm-smoke
Bug: 168766580
Change-Id: Id43fb2a1e82ef6e21a540e0af551b0fee430353f