Ignore paths in CSP matching after redirects
When a ResourceRequest has a redirect chain before it, set an
ignoreSourcePaths flag that gets passed all the way down to the CSP
source matching, which will ignore paths in sources when the resource
URL is the result of a redirect.
BUG=452821
Review URL: https://codereview.chromium.org/960833003
git-svn-id: svn://svn.chromium.org/blink/trunk@191574 bbb929c8-8fbe-4397-9dbb-9b2b20218538