Allow multiple logging::LogMessage{Handler,Listener}s

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index 7783a262a27b36201331f3184c5823e7e952f6f8..849baa5ec6c654dcd32eccb64a31c4f5148a3473 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -911,6 +911,10 @@ void RenderFrameHostImpl::OnAddMessageToConsole(
   if (delegate_->AddMessageToConsole(level, message, line_no, source_id))
     return;
 
+  // In order for CSP violation detections in the tests to work, console
+  // messages must be forwarded to logging::LogMessage().
+  // Ref: https://crbug.com/638050
+
   // Pass through log level only on WebUI pages to limit console spew.
   const bool is_web_ui =
       HasWebUIScheme(delegate_->GetMainFrameLastCommittedURL());