ProcessSearchError gives poor error message

Fix committed into lp:autopilot at revision 417, scheduled for release in autopilot, milestone 1.4

This bug was fixed in the package autopilot - 1.4+14.04.20140129-0ubuntu1

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autopilot (1.4+14.04.20140129-0ubuntu1) trusty; urgency=low

  [ Barry Warsaw ]
  * Make Autopilot tracepoint extension module compatible with python 3.
    (LP: #1266574)

  [ Steve Langasek ]
  * Fix the autopilot-touch package to be Architecture: all instead of
    having it be Architecture: any with a wrong architecture exclusion
    of a dependency.

  [ Christopher Lee ]
  * Handle xml parse exception nicely as well as add some nicer
    logging/feedback.
  * Fixes issues with load_test_suite_from_name.
  * Make autopilot able to run it's own tests again.
  * When setting up logging take into account not all modes/commands
    have a verbose argument.
  * Fixes the issue when listing an non-existent test suite raised an
    uncaught exception. .
  * Minor fix for a failing functional test, now passes under python 2
    and 3.
  * Minor fixup of TypeError in platform docs re: skipping tests.
  * Add details to Faq docs re: launching (click) applications. (LP:
    #1257148)
  * Refactor of the application launching code (incl. tests).
  * Fix issue with launching click app and added test to cover it.
  * Ensure test discovery looks and uses cwd before system path.
  * Attempts to use the newer version call to 'launch_uris_as_manager',
    falls back to the simpler 'launch_uris' if that fails.
  * Click applications now provide application_name to
    get_proxy_object_for_existing_process. (LP: #1274292)

  [ Thomi Richards ]
  * Fix tox.ini config file to restrict flake8 runs to the autopilot/
    directory.
  * Make autopilot fail when no command is specified. (LP: #1255334)
  * Move the contents of the 'autopilot' script into autopilot/run.py,
    and make setuptools generate the autopilot script for us.
  * Make autopilot understand how the "-qt=XXX" option works. (LP:
    #1255405)
  * Handle xml parse exception nicely as well as add some nicer
    logging/feedback.
  * Fix autopilot test case loading. (LP: #1255752, #1255659)
  * Move the BackendException class to solve a circular import.
  * Make autopilot support subunit bytestream output. (LP: #1255662)
  * Make autopilot able to run it's own tests again.
  * Remove an incorrect comment from the source code.
  * Fix some unit tests that were printing to stdout.
  * Lay the groundwork for attaching files to test results.
  * Fix failing tests in python3.
  * Add click package log file to test result. (LP: #1257453)
  * Add a simple shell script that can be used to generate unit test
    coverage for autopilot itself.
  * Add unit tests for common input code.
  * Remove some unused code code in the type support unit tests.
  * Don't include test lines in coverage count.
  * Add a few missing test cases, increase test case coverage.
  * Add unit tests for process snapshot support.
  * A few tweaks to the make_coverage script to make it a bit more
    useful.
  * Fix issue with launching click app and added test to cover it.
  * Add suppoprt for debugging profiles to autopilot.
  * Add ability to control autopilot timeout values from the command
    line. Refactor code so I can add testing to au...