Clang update script: support fetching pre-built CMake on Mac
Clang update script: support fetching pre-built CMake on Mac

Both cmake310_Linux.tgz and cmake310_Darwin.tgz exist now.
I'll remove the poorly named cmake310.tgz when this has landed.

BUG=452726

Review URL: https://codereview.chromium.org/1073673002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#324372}

Chilledheart/chromium,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,chuan9/chromium-crosswalk,Just-D/chromium-1,PeterWangIntel/chromium-crosswalk,ltilve/chromium,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,chuan9/chromium-crosswalk,Chilledheart/chromium,hgl888/chromium-crosswalk,Chilledheart/chromium,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,hgl888/chromium-crosswalk,Just-D/chromium-1,ltilve/chromium,PeterWangIntel/chromium-crosswalk,Chilledheart/chromium,PeterWangIntel/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,Just-D/chromium-1,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,Just-D/chromium-1,Fireblend/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,ltilve/chromium,ltilve/chromium,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,ltilve/chromium,PeterWangIntel/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,Fireblend/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,hgl888/chromium-crosswalk,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,TheTypoMaster/chromium-crosswalk,Fireblend/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk,ltilve/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,ltilve/chromium,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,Just-D/chromium-1,ltilve/chromium,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,Chilledheart/chromium,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Fireblend/chromium-crosswalk,Just-D/chromium-1,ltilve/chromium,chuan9/chromium-crosswalk,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk