Add autoBuildCacheRatio to master.client.dart.
Add autoBuildCacheRatio to master.client.dart.

BUG=265331
TBR=ilevy@chromium.orgTBR=ilevy@chromium.org

Review URL: https://chromiumcodereview.appspot.com/21025003

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@214187 0039d316-1c4b-4281-b951-d872f2087c98

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