Improve stability - return null when LastAccessedProvider no longer exist

From OEM's feedback, there is a suggestion for stability enahncement
In case to prevent NPE in for loop, we check ResolveInfo before add

Change-Id: I574c5cab7a3a1af1f5400c9b10c2d836c7d360d4
Fix: 122817012
Test: atest DocumentsUITests
1 file changed