CommandLineTest.ProgramQuotes: Fix crash-prone test.

CommandLineTest.ProgramQuotes: Fix crash-prone test.

Previously, this test would crash if the output wasn't quoted properly
(since it assumes that cmd_string.length() >= program_string.length() +
2). Instead, directly compare the string with the expected output. This
also guards against the possibility of mis-constructing the expected
string.

Committed: https://crrev.com/b937b24239d36fb4cdfeb98b2db818e4304dd8b4
Cr-Commit-Position: refs/heads/master@{#296350}

[Matt Giuca, 2014-09-23 08:28:27]

mgiuca@chromium.org changed reviewers:
+ mark@chromium.org

[Mark Mentovai, 2014-09-23 12:25:45]

LGTM

[Matt Giuca, 2014-09-24 04:18:43]

The CQ bit was checked by mgiuca@chromium.org

[commit-bot: I haz the power, 2014-09-24 04:19:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/589393002/1

[commit-bot: I haz the power, 2014-09-24 04:55:37]

Committed patchset #1 (id:1) as ba61e7ee5e35facf09aa99b5988b56ff7d87db3a

[commit-bot: I haz the power, 2014-09-24 04:56:14]

Patchset 1 (id:??) landed as
https://crrev.com/b937b24239d36fb4cdfeb98b2db818e4304dd8b4
Cr-Commit-Position: refs/heads/master@{#296350}