Make chromium.perf Linux official produce 64-bit builds.
Make chromium.perf Linux official produce 64-bit builds.

It produced 64-bit builds prior to r218856 and cross compiling is broken on the
bot.

BUG=223572,271252

Review URL: https://chromiumcodereview.appspot.com/23358004

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@219339 0039d316-1c4b-4281-b951-d872f2087c98

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