Pass RapporService to content/browser/

content/browser/renderer_host/render_widget_host_delegate.h

Index: content/browser/renderer_host/render_widget_host_delegate.h
diff --git a/content/browser/renderer_host/render_widget_host_delegate.h b/content/browser/renderer_host/render_widget_host_delegate.h
index 80fbea2d0d76ebc7005c1eee90b9854ac2b4c88a..7395af293fc1d7f8a4ef048ab8c86cd0c5bf0d11 100644
--- a/content/browser/renderer_host/render_widget_host_delegate.h
+++ b/content/browser/renderer_host/render_widget_host_delegate.h
@@ -236,6 +236,9 @@ class CONTENT_EXPORT RenderWidgetHostDelegate {
   virtual void FocusOwningWebContents(
       RenderWidgetHostImpl* render_widget_host) {}
 
+  // Returns the eTLD+1 of the current page.
+  virtual std::string GetRapporCommittedUrl();

[ncarter (slow), 2016/12/01 22:33:32]

As we were discussing before, this looks out of place here here because the URL
is not widget state -- widgets don't navigate or load things from the network.

However, I had a look at your motivating CL, and understand now the problem that
this solves. What's happening is that we have gathered some stats way down in a
stats-tracking helper, and we need to percolate up to the delegate to add the
eTLD+1 context.

What if we structured the method like this:

// Augment a Rappor sample with eTLD+1 context. The caller is still responsible
// for logging the sample to the RapporService. Returns false if the eTLD+1
// is not known for |render_widget_host|.
virtual bool AddDomainInfoToRapporSample(
    RenderWidgetHostImpl* render_widget_host,
    rappor::Sample* sample);

Does that work?

[Navid Zolghadr, 2016/12/02 20:47:35]

Sure. Sounds good. But why do I need RenderWidgetHostImpl*?

[ncarter (slow), 2016/12/05 19:50:50]

There can be arbitrarily many RenderWidgetHosts inside a WebContents, all
sharing a delegate, so I default to expecting that methods on the delegate will
pass the pointer. However, it's okay to plumb this as needed.

+
  protected:
   virtual ~RenderWidgetHostDelegate() {}
 };