Phoshor Test failure when PHOSPHOR_TRACING_START environment variable is set

When the PHOSPHOR_TRACING_START environment variable is set, results in the following three test failures:

• export_test
• trace_log_test
• memory_usage_test

Test Output:

Test project /Users/danielowen/master/build/phosphor
Start 1: category_registry_test
1/12 Test #1: category_registry_test ........... Passed 0.02 sec
Start 2: export_test
2/12 Test #2: export_test ......................***Failed 0.02 sec
Start 3: memory_test
3/12 Test #3: memory_test ...................... Passed 0.01 sec
Start 4: sentinel_test
4/12 Test #4: sentinel_test .................... Passed 0.01 sec
Start 5: string_utils_test
5/12 Test #5: string_utils_test ................ Passed 0.01 sec
Start 6: trace_argument_test
6/12 Test #6: trace_argument_test .............. Passed 0.01 sec
Start 7: trace_event_test
7/12 Test #7: trace_event_test ................. Passed 0.01 sec
Start 8: trace_buffer_test
8/12 Test #8: trace_buffer_test ................ Passed 0.03 sec
Start 9: trace_config_test
9/12 Test #9: trace_config_test ................ Passed 0.01 sec
Start 10: trace_log_test
10/12 Test #10: trace_log_test ...................***Failed 0.01 sec
Start 11: memory_usage_test
11/12 Test #11: memory_usage_test ................***Failed 0.94 sec
Start 12: macro_test
12/12 Test #12: macro_test ....................... Passed 0.02 sec

75% tests passed, 3 tests failed out of 12

Total Test time (real) = 1.09 sec

The following tests FAILED:
2 - export_test (Failed)
10 - trace_log_test (Failed)
11 - memory_usage_test (Failed)
Errors while running CTest