Fix step name of startup_warm and startup_cold tests.
Fix step name of startup_warm and startup_cold tests.

BUG=262933,237696

Review URL: https://chromiumcodereview.appspot.com/22926015

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@219050 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build