[DevTools] Rework DevToolsSession interaction with domain handlers.

content/browser/devtools/protocol/security_handler.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/devtools/protocol/security_handler.h"
 
 #include <string>
 
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/public/browser/navigation_controller.h"
@@ skipping 39 matching lines @@
         .SetSummary(it.summary)
         .SetDescription(it.description)
         .SetHasCertificate(it.has_certificate)
         .Build());
   }
 }
 
 }  // namespace
 
 SecurityHandler::SecurityHandler()
-    : enabled_(false),
+    : DevToolsDomainHandler(Security::Metainfo::domainName),
+      enabled_(false),
       host_(nullptr) {
 }
 
 SecurityHandler::~SecurityHandler() {
 }
 
 void SecurityHandler::Wire(UberDispatcher* dispatcher) {
   frontend_.reset(new Security::Frontend(dispatcher->channel()));
   Security::Dispatcher::wire(dispatcher, this);
 }
@@ skipping 86 matching lines @@
       web_contents->GetController().GetVisibleEntry()->GetSSL().certificate;
   if (!certificate)
     return Response::Error("Could not find certificate");
   web_contents->GetDelegate()->ShowCertificateViewerInDevTools(
       web_contents, certificate);
   return Response::OK();
 }
 
 }  // namespace protocol
 }  // namespace content