Add 'web_accessible_resource" keyword for version 2 extension manifests. This makes extension resources web accessible only when explicitly intended. Behavior is unaffected unless an extension specifies a manifest_version of 2 or more. 

BUG=46002
TEST=ExtensionResourceRequestPolicyTest.WebAccessibleResources
Review URL: http://codereview.chromium.org/8849010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@115401 0039d316-1c4b-4281-b951-d872f2087c98
21 files changed