Adding an OWNERS file for tools/build/.
Adding an OWNERS file for tools/build/.

BUG=79402

Review URL: http://codereview.chromium.org/6874032

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@82160 0039d316-1c4b-4281-b951-d872f2087c98

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