Assert no-write access for Android/<data|obb> directories

'Android/<data|obb>' directories may not be executable, depending on the
mount/volume. However, these directories should never be writable, hence
we can always test no-write access for these directories.

Changed testAllWalkingUpTreeReadOnly to assertDirNoWriteAccess for
Android/<data|obb> path instead of assertDirReadOnlyAccess

Bug: 160211885
Test: atest ExternalStorageHostTest#testExternalStorageRead29
Merged-In: I6140f79f3cc5f23397607c6e220aee20894d7948
Change-Id: I6140f79f3cc5f23397607c6e220aee20894d7948
1 file changed