Validate user-supplied URIs in DocumentsProvider calls

Some URIs are used without validating their authorities which can lead
to exploitation by malicious apps.

Bug: 157294893
Test: Manual using test app in b/157294893
Change-Id: I799509ed5ff7e69140e84d796fe7f96d9dbfd32f
Merged-In: I799509ed5ff7e69140e84d796fe7f96d9dbfd32f
(cherry picked from commit 75f984bd)