Fix memory leak in ToolbarActionBar

Caused when there are multiple calls to
setSupportActionBar() (i.e. fragments). ToolbarActionBar
currently just wraps the Window's current Callback. Which
means that for every setSupportActionBar() call, we're
re-wrapping a ToolbarActionBar Window.Callback wrapper.

This CL fixes it by making sure that we always wrap the
correct 'root' Window.Callback.

BUG: 21914909

Change-Id: I8f21b94d60eb488630b1fe7377ba62d3608accef
3 files changed