[DevTools] Support multiple sessions in content/ domain handlers

content/browser/devtools/protocol/page_handler.cc

 // Copyright 2014 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/page_handler.h"
 
 #include <algorithm>
 #include <memory>
 #include <string>
 #include <utility>
@@ skipping 91 matching lines @@
       frames_in_flight_(0),
       navigation_throttle_enabled_(false),
       next_navigation_id_(0),
       host_(nullptr),
       weak_factory_(this) {}
 
 PageHandler::~PageHandler() {
 }
 
 // static
-PageHandler* PageHandler::FromSession(DevToolsSession* session) {
-  return static_cast<PageHandler*>(
-      session->GetHandlerByName(Page::Metainfo::domainName));
+std::vector<PageHandler*> PageHandler::ForAgentHost(
+    DevToolsAgentHostImpl* host) {
+  return DevToolsSession::HandlersForAgentHost<PageHandler>(
+      host, Page::Metainfo::domainName);
 }
 
 void PageHandler::SetRenderFrameHost(RenderFrameHostImpl* host) {
   if (host_ == host)
     return;
 
   RenderWidgetHostImpl* widget_host =
       host_ ? host_->GetRenderWidgetHost() : nullptr;
   if (widget_host) {
     registrar_.Remove(
@@ skipping 449 matching lines @@
 Response PageHandler::StopLoading() {
   WebContentsImpl* web_contents = GetWebContents();
   if (!web_contents)
     return Response::InternalError();
   web_contents->Stop();
   return Response::OK();
 }
 
 }  // namespace protocol
 }  // namespace content