When navigating cross-origin a speculative RenderFrameHost (RFH) and
CefFrameHostImpl is created in the browser process for the new frame object
created in a new renderer process. The FrameAttached message then arrives for
the speculative RFH, and as a consequence interfaces are bound between the new
CefFrameHostImpl and the speculative RFH. If the pending navigation commits
then the existing RFH will be replaced with the previously speculative RFH.
Since interfaces are already bound we must keep the new CefFrameHostImpl. This
means that frame objects (including for the main frame) will now always change
after cross-origin navigation, and the old frame object will be invalidated.
This change introduces a few minor CEF API behavior changes:
- A CefProcessMessage object cannot be reused after being passed to
SendProcessMessage.
- The |extra_info| argument to CefRenderProcessHandler::OnBrowserCreated may
now be NULL.
Where appropriate, we now utilize the default UTF string encoding format and
shared memory to reduce copies and conversions for the cross-process
transfer of arbitrary-length strings. For example, CefFrame::GetSource/GetText
now involves zero UTF conversions and zero copies in the browser process for
the CefString delivered to CefStringVisitor::Visit().
Marshall Greenblatt