Kill all versions of the iOS simulator, regardless of Xcode version
Kill all versions of the iOS simulator, regardless of Xcode version

This relands 2df4f9ce10d3cd5b030806ebf2951bc09d04b8a8 in a way that will work.

BUG=504097
TBR=justincohen

Review URL: https://codereview.chromium.org/1206633009.

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@295829 0039d316-1c4b-4281-b951-d872f2087c98

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