Fix showing keyboard without editor focused in some cases (2/2)

As CL[1] mentioned issue symptom, we also need to remove
STATE_ALWAYS_VISIBLE in EditTextPreference
and using new WindowInsets API to show soft-keyboard, to prevent the
keyboard may be shown without focusing editor case.

[1]: I37ae6e30d1de581ba15131c2a90396b3a522a4d6

Fix: 165910518
Test: atest CtsInputMethodTestCases
Test: manual as issue steps
1. Enter Dialer-> Menu -> Settings-> calling accounts -> Fixed Dialing Numbers
2. Tap change pin2 code, input old pin2 -> pressing ok button
3. Check if password keyboard shown

Change-Id: I763838fb7b887e09b46b1fb2360a515b77de8dd4