Support "canary" as a version string modifier in Mac Chrome.
Support "canary" as a version string modifier in Mac Chrome.

BUG=79814
TEST=none
Review URL: http://codereview.chromium.org/6873062

git-svn-id: http://src.chromium.org/svn/trunk/src@82060 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: a465467454cd8391ce2aadb234a2e8f3c5ada826
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