base

Fix code example in testing-support-library.

Note: mDevice is a variable, there is additional brackets.

Bug:
https://code.google.com/p/android/issues/detail?id=206043

Change-Id: I8e88a6144f1ede1d45262ff034159de524c24b70
(cherry picked from commit 6b1853008eac7f64634d7a632869fc6248053d18)