Add bookkeeping test for empty callstack. am: debe648a37 am: 44f01b5bf7 am: 8c3dbd9ea2 am: 76d5c0ca66 am: c1da83f332
Add bookkeeping test for empty callstack. am: debe648a37 am: 44f01b5bf7 am: 8c3dbd9ea2 am: 76d5c0ca66
am: c1da83f332

Change-Id: I9d07ebbc77bd9c4cbfa406bb074f83d364655a24

google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto