Flush stdout when pyauto perf tests print perf results on non-ChromeOS platforms.
Flush stdout when pyauto perf tests print perf results on non-ChromeOS platforms.

When the tests in perf.py run through buildbot on non-ChromeOS platforms such
as Windows, sometimes the specially-formatted perf result output is corrupted
by interleaved output due to buffering.  This problem was previously fixed
on ChromeOS:

http://codereview.chromium.org/8772022/

The current CL makes the same fix for non-ChromeOS platforms.

BUG=None
TEST=None

Review URL: https://chromiumcodereview.appspot.com/9428038

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@123081 0039d316-1c4b-4281-b951-d872f2087c98

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