Update perf expectations to use new format.
Update perf expectations to use new format.

This updates the following systems to use the new improve/regress
format:
  - linux-release
  - linux-release-hardy
  - mac10.5
  - mac10.6
  - vista-release-dual-core
  - vista-release-single-core
  - xp-release-dual-core
  - xp-release-single-core

BUG=none
TEST=perf steps run correctly

Review URL: http://codereview.chromium.org/3148028

git-svn-id: http://src.chromium.org/svn/trunk/src@56872 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: fd5d54d84bb8874d940a8f943705f44b820b4823
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser