It should be possible to filter network events of a webview

[mildred]

The webview should allow its container to filter all network events. In particular, this should permit:

• To use SSL client certificates
• To have different cookie jars (one for each private tab, and one for normal navigation for instance)
• To have different history settings (private browsing again)
• The origin of the request should be known (related resource (image, script, css, video, ...), XMLHttpRequest, form submit, follow link)