100644 blob 992c735f50920d6f1af7d096ed428a0b314830a9	user_activity_detector.cc
100644 blob dab5bc407a01cda3c712b2c95c43ed7f64fd8fb3	user_activity_detector.h
100644 blob 9002a20ba21c5bdb3c11c4ac45016a1f1a9e7f70	user_activity_detector_unittest.cc
100644 blob f6b98d210afdabb8ca580b7d094dbc68700bd24e	user_activity_observer.h