Revert "Add basic support for Ctrl-Z to editable TextViews"

This reverts commit 9201e797833f35b9afb219f88c10d3b6fda02a4e.

It causes crashes on typing after device orientation change.

Bug: 19332904
Bug: 19505388
Change-Id: I0d9fb728eb6f8d591beb35fab333c0a182e24542
6 files changed