Chrome Releases reports:
11 security fixes in this release, including:
 High CVE-2015-1209: Use-after-free in DOM. Credit to Maksymillian.  High CVE-2015-1210: Cross-origin-bypass in V8 bindings. Credit to anonymous.  High CVE-2015-1211: Privilege escalation using service workers. Credit to anonymous.  CVE-2015-1212: Various fixes from internal audits, fuzzing and other initiatives.