Fix explicit intent for instant app tests.

Add null checks to ensure RemoteInlineSuggestionRenderService is not
being called if service component cannot be found.

Fixes: 150315090
Fixes: 150318779
Fixes: 150319014
Fixes: 150039791
Fixes: 150304313
Test: atest CtsAutoFillServiceTestCases --instant
Test: atest CtsInputMethodServiceHostTestCases --instant
Change-Id: Ie8c84b12a0dc8e7415d94e4edb919de27827b799