Web Bluetooth New Permissions Backend

This virtual test suite runs content_shell with --enable-features=WebBluetoothNewPermissionsBackend. This flag enables the Web Bluetooth tests to use the FakeBluetoothDelegate interface for granting and checking permissions. This class emulates the behavior of the new Web Bluetooth permissions backend based on ObjectPermissionContextBase.

The new permissions backend is implemented as part of the Web Bluetooth Persistent Permissions project.

TODO(https://crbug.com/589228): Remove this virtual test suite when the WebBluetoothNewPermissionsBackend flag is enabled by default.