Bug 925873 - Make mochitest emit TEST-UNEXPECTED-FAIL on non-zero exit code. r=ted.

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extra : rebase_source : 17eb855e9bdc1b22c1187ede1dbb1b820f230290
Bug 929024 - Fix ASan symbolizing for mochitests. r=ted

--HG--
extra : rebase_source : f6b4ee3a5d84ba1987f2a35abe9b28c1d45efb2e