Restrict CM API interface request and message dispatch.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 52ddbab340bdc1211418e09c4e8ef738543b3935..269e54380f46e9ac98a896ae9751f67fa75ef46a 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -4371,8 +4371,16 @@ void WebContentsImpl::OnAssociatedInterfaceRequest(
     const std::string& interface_name,
     mojo::ScopedInterfaceEndpointHandle handle) {
   auto it = binding_sets_.find(interface_name);
-  if (it != binding_sets_.end())
+  if (it != binding_sets_.end()) {
     it->second->OnRequestForFrame(render_frame_host, std::move(handle));
+    return;
+  }
+
+  service_manager::BindSourceInfo source_info(
+      render_frame_host->GetProcess()->GetChildIdentity(),
+      service_manager::CapabilitySet());
+  GetContentClient()->browser()->BindAssociatedInterfaceRequestFromFrame(
+      render_frame_host, source_info, interface_name, std::move(handle));
 }
 
 const GURL& WebContentsImpl::GetMainFrameLastCommittedURL() const {