Attach a SecurityStyle to each request in ResourceLoader
This CL adds a SecurityStyle to the serialized security information that
is sent with each request from the browser to the renderer. The
SecurityStyle describes the individual resource, not any bigger-picture
concerns like mixed content. The per-request SecurityStyle will be
displayed in DevTools to help developers diagnose SSL issues on
subresources.
BUG=502118, 445234
Review URL: https://codereview.chromium.org/
1244863003
Cr-Commit-Position: refs/heads/master@{#340762}