Grow lists by a factor of 2 instead of 1.5 on a resize.
Grow lists by a factor of 2 instead of 1.5 on a resize.

For zone lists this avoids resizing and reduces overall allocation
in most cases (especially for small lists).
Review URL: https://chromiumcodereview.appspot.com/9323078

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@10613 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh