Restrict CM API interface request and message dispatch.

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
diff --git a/content/public/browser/content_browser_client.cc b/content/public/browser/content_browser_client.cc
index 529f49fa7ff5469f6a1b4a0858b5de96a5ee8a2e..516fde253dbd898fe5c85ddf40fcd39fddd3664c 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -390,6 +390,13 @@ std::string ContentBrowserClient::GetServiceUserIdForBrowserContext(
   return base::GenerateGUID();
 }
 
+bool ContentBrowserClient::BindAssociatedInterfaceRequestFromFrame(
+    RenderFrameHost* render_frame_host,
+    const std::string& interface_name,
+    mojo::ScopedInterfaceEndpointHandle* handle) {
+  return false;
+}
+
 ControllerPresentationServiceDelegate*
 ContentBrowserClient::GetControllerPresentationServiceDelegate(
     WebContents* web_contents) {