title: Intercept HTTP request body from chrome extension
body: <p>I'm aware that <code>chrome.webRequest.onBeforeRequest</code> allows a request to be intercepted, analyzed and blocked, but it only allows access to the request headers, and not the request body (as far as i know). </p>
  
  <p>Sample use case: think intercepting form values.</p>
  
  <p>It seems there is a API change proposal <a href="http://www.chromium.org/developers/design-documents/extensions/proposed-changes/apis-under-development/notifications-of-web-request-and-navigation#TOC-Accessing-request-and-response-bodi">here</a> suggesting exactly this.</p>
  
  <p>Is there another way this could be accomplished? </p>
  
  <p>Thanks.</p>