Revert of Never send a referrer header if the referrer is not a web url (https://codereview.chromium.org/136583002/)

Reason for revert:
This is the probable cause for the failing browser test CorrectReferrer. See:

http://build.chromium.org/p/chromium.webkit/builders/Linux%20Tests%20%28dbg%29/builds/1302/steps/browser_tests/logs/CorrectReferrer

http://build.chromium.org/p/chromium.webkit/builders/Mac10.8%20Tests/builds/5398/steps/browser_tests/logs/CorrectReferrer

http://build.chromium.org/p/chromium.webkit/builders/Win7%20Tests/builds/543/steps/browser_tests/logs/CorrectReferrer

Original issue's description:
> Never send a referrer header if the referrer is not a web url
> 
> BUG=none
> R=abarth@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=165085

TBR=abarth@chromium.org,jochen@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=none

Review URL: https://codereview.chromium.org/133863003

git-svn-id: svn://svn.chromium.org/blink/trunk@165090 bbb929c8-8fbe-4397-9dbb-9b2b20218538