NULL inputType text fields should never show the IME.

Bug 3381317

Changes made in https://android-git.corp.google.com/g/#change,91880
displayed the IME onFocus. However, the test was not consistent to what
is done in touch event. textIsEditable is now checked too.

Change-Id: If11382c1c90a557839b87d62494253470c42b621