fx-team $ ./mach mochitest-browser browser/devtools/profiler/test/
obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest/runtests.py
obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest
/Users/akovalyov/Source/fx-team/obj-x86_64-apple-darwin12.3.0/obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest
/Users/akovalyov/Source/fx-team/obj-x86_64-apple-darwin12.3.0/obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest
Error running mach:

    ['mochitest-browser', 'browser/devtools/profiler/test/']

The error occurred in code that was called by the mach command. This is either
a bug in the called code itself or in the way that mach is calling it.

You should consider filing a bug for this issue.

If filing a bug, please include the full output of mach, including this error
message.

The details of the failure are as follows:

OSError: [Errno 2] No such file or directory: '/Users/akovalyov/Source/fx-team/obj-x86_64-apple-darwin12.3.0/obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest'

  File "/Users/akovalyov/Source/fx-team/testing/mochitest/mach_commands.py", line 209, in run_mochitest_browser
    return self.run_mochitest(test_file, 'browser', **kwargs)
  File "/Users/akovalyov/Source/fx-team/testing/mochitest/mach_commands.py", line 226, in run_mochitest
    **kwargs)
  File "/Users/akovalyov/Source/fx-team/testing/mochitest/mach_commands.py", line 90, in run_mochitest_test
    runner = mochitest.Mochitest(automation)
  File "obj-x86_64-apple-darwin12.3.0/_tests/testing/mochitest/runtests.py", line 526, in __init__
    os.chdir(self.SCRIPT_DIRECTORY)