Add media_perf step to Linux Perf (2).
Add media_perf step to Linux Perf (2).

BUG=79636
TEST=media_perf runs on Linux Perf (2)

Review URL: http://codereview.chromium.org/6880054

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@82764 0039d316-1c4b-4281-b951-d872f2087c98

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