Add tests for MANAGE_EXTERNAL_STORAGE

We previously had 1 basic test case to ensure that apps with the
permission do bypass MediaProvider restrictions when creating a file.
This CL adds more test cases to ensure apps with the permission have
full access even to other apps' contents: read, write, delete and
rename.

Test: atest FuseDaemonHostTest
Fixes: 146778323
Change-Id: Ie6d5e9fd24206e8de32820fd6cd40515ed8d9fd9
3 files changed