Add manifest file for only DocumentsUI res for tests

1. Move some functional tests from unit tests.
2. The manifest will be used by unit tests, manifest does not include the providers, because they conflict with the providers from real documentsui

Test: atest DocumentsUIGoogleTests
Fixes: 155692975

Change-Id: I97f2e0a7f601e7c01c7d36689540658c1930913a