Bug 1347010: UI for only displaying files in MTP directories. For now, "Show all files" is always visible at start and non-MTP directories are not viewable. After clicking "Show all files", all files are shown.
TODO:
- "Show all files" only when user has set PIN/password, if not all files are automatically shown
- When "Show all files" clicked query PIN/password from user and if it's valid only then display all files