- Change rclone/fs interfaces to accept context.Context
- Update interface implementations to use context.Context
- Change top level usage to propagate context to lover level functions
Context propagation is needed for stopping transfers and passing other
request-scoped values.
This bug was introduced by the v3 API conversion in 07f20dd1fd.
The problem was that dircache.FindPath doesn't work for the root directory.
This adds an internal error for dircache.FindPath being called with
the root directory. This makes a failing test, which the fix to the
drive backend fixes.
This also improves the DirCache integration test.