Hide SoftInput when INVALID_DISPLAY

We only prevent to show soft input in
IMMS#startInputUncheckedLocked when
DISPLAY_IME_POLICY_HIDE is set.

If a display with DISPLAY_IME_POLICY_HIDE,
we should hide the soft input anyway.

Bug: 199991634
Test: atest CtsInputMethodTestCases
Test: Verify as following steps:
1) adb shell wm size 800x1280
2) adb shell wm density 213
3) atest MultiDisplaySystemDecorationTests#\
   testDisplayPolicyImeHideImeNoSystemDecorations

Change-Id: I3ab03667c28ec5beb6c3332aceaae4a63cd7309a