[DevTools] Move DevToolsClientHost functionality out of DevToolsFrontendHost.

DevToolsFrontendHost is just a transport now.

Next step is to remove HandleMessageFromDevToolsFrontendToBackend,
make it one of the embedder messages, and allow embedder to talk
to backend in itself.

BUG=398046

Review URL: https://codereview.chromium.org/427143003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@287027 0039d316-1c4b-4281-b951-d872f2087c98

14 files changed, 255 insertions, 233 deletions

diff --git a/chrome/browser/devtools/devtools_ui_bindings.cc b/chrome/browser/devtools/devtools_ui_bindings.cc
index dcef0cb..620f432 100644
--- a/chrome/browser/devtools/devtools_ui_bindings.cc
+++ b/chrome/browser/devtools/devtools_ui_bindings.cc
@@ -259,6 +259,16 @@ void DevToolsUIBindings::FrontendWebContentsObserver::WebContentsDestroyed() {
 
 void DevToolsUIBindings::FrontendWebContentsObserver::RenderProcessGone(
     base::TerminationStatus status) {
+  switch (status) {
+    case base::TERMINATION_STATUS_ABNORMAL_TERMINATION:
+    case base::TERMINATION_STATUS_PROCESS_WAS_KILLED:
+    case base::TERMINATION_STATUS_PROCESS_CRASHED:
+      content::DevToolsManager::GetInstance()->ClientHostClosing(
+          devtools_bindings_);
+      break;
+    default:
+      break;
+  }
   devtools_bindings_->delegate_->RenderProcessGone();
 }
 
@@ -266,10 +276,13 @@ void DevToolsUIBindings::FrontendWebContentsObserver::AboutToNavigateRenderView(
     content::RenderViewHost* render_view_host) {
   content::NavigationEntry* entry =
       web_contents()->GetController().GetActiveEntry();
-  if (devtools_bindings_->url_ == entry->GetURL())
-    content::DevToolsClientHost::SetupDevToolsFrontendClient(render_view_host);
-  else
+  if (devtools_bindings_->url_ == entry->GetURL()) {
+    devtools_bindings_->frontend_host_.reset(
+        content::DevToolsFrontendHost::Create(
+            render_view_host, devtools_bindings_));
+  } else {
     delete devtools_bindings_;
+  }
 }
 
 void DevToolsUIBindings::FrontendWebContentsObserver::
@@ -314,8 +327,6 @@ DevToolsUIBindings::DevToolsUIBindings(content::WebContents* web_contents,
   frontend_contents_observer_.reset(new FrontendWebContentsObserver(this));
   web_contents_->GetMutableRendererPrefs()->can_accept_load_drops = false;
 
-  frontend_host_.reset(content::DevToolsClientHost::CreateDevToolsFrontendHost(
-      web_contents_, this));
   file_helper_.reset(new DevToolsFileHelper(web_contents_, profile_));
   file_system_indexer_ = new DevToolsFileSystemIndexer();
   extensions::ChromeExtensionWebContentsObserver::CreateForWebContents(
@@ -342,8 +353,7 @@ DevToolsUIBindings::DevToolsUIBindings(content::WebContents* web_contents,
 }
 
 DevToolsUIBindings::~DevToolsUIBindings() {
-  content::DevToolsManager::GetInstance()->ClientHostClosing(
-      frontend_host_.get());
+  content::DevToolsManager::GetInstance()->ClientHostClosing(this);
 
   for (IndexingJobsMap::const_iterator jobs_it(indexing_jobs_.begin());
        jobs_it != indexing_jobs_.end(); ++jobs_it) {
@@ -354,10 +364,7 @@ DevToolsUIBindings::~DevToolsUIBindings() {
   SetDevicesUpdatesEnabled(false);
 }
 
-void DevToolsUIBindings::InspectedContentsClosing() {
-  delegate_->InspectedContentsClosing();
-}
-
+// content::NotificationObserver overrides ------------------------------------
 void DevToolsUIBindings::Observe(int type,
                                  const content::NotificationSource& source,
                                  const content::NotificationDetails& details) {
@@ -365,7 +372,9 @@ void DevToolsUIBindings::Observe(int type,
   UpdateTheme();
 }
 
-void DevToolsUIBindings::DispatchOnEmbedder(const std::string& message) {
+// content::DevToolsFrontendHost::Delegate implementation ---------------------
+void DevToolsUIBindings::HandleMessageFromDevToolsFrontend(
+    const std::string& message) {
   std::string method;
   base::ListValue empty_params;
   base::ListValue* params = &empty_params;
@@ -394,6 +403,27 @@ void DevToolsUIBindings::DispatchOnEmbedder(const std::string& message) {
   }
 }
 
+void DevToolsUIBindings::HandleMessageFromDevToolsFrontendToBackend(
+    const std::string& message) {
+  content::DevToolsManager::GetInstance()->DispatchOnInspectorBackend(
+      this, message);
+}
+
+// content::DevToolsClientHost implementation ---------------------------------
+void DevToolsUIBindings::DispatchOnInspectorFrontend(
+    const std::string& message) {
+  if (frontend_host_)
+    frontend_host_->DispatchOnDevToolsFrontend(message);
+}
+
+void DevToolsUIBindings::InspectedContentsClosing() {
+  delegate_->InspectedContentsClosing();
+}
+
+void DevToolsUIBindings::ReplacedWithAnotherClient() {
+}
+
+// DevToolsEmbedderMessageDispatcher::Delegate implementation -----------------
 void DevToolsUIBindings::ActivateWindow() {
   delegate_->ActivateWindow();
 }
diff --git a/chrome/browser/devtools/devtools_ui_bindings.h b/chrome/browser/devtools/devtools_ui_bindings.h
index 8ebd805..2ec6de5 100644
--- a/chrome/browser/devtools/devtools_ui_bindings.h
+++ b/chrome/browser/devtools/devtools_ui_bindings.h
@@ -18,7 +18,7 @@
 #include "chrome/browser/devtools/devtools_file_system_indexer.h"
 #include "chrome/browser/devtools/devtools_targets_ui.h"
 #include "content/public/browser/devtools_client_host.h"
-#include "content/public/browser/devtools_frontend_host_delegate.h"
+#include "content/public/browser/devtools_frontend_host.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "ui/gfx/size.h"
@@ -34,9 +34,10 @@ class WebContents;
 
 // Base implementation of DevTools bindings around front-end.
 class DevToolsUIBindings : public content::NotificationObserver,
-                           public content::DevToolsFrontendHostDelegate,
+                           public content::DevToolsFrontendHost::Delegate,
                            public DevToolsEmbedderMessageDispatcher::Delegate,
-                           public DevToolsAndroidBridge::DeviceCountListener {
+                           public DevToolsAndroidBridge::DeviceCountListener,
+                           public content::DevToolsClientHost {
  public:
   static GURL ApplyThemeToURL(Profile* profile, const GURL& base_url);
 
@@ -65,7 +66,6 @@ class DevToolsUIBindings : public content::NotificationObserver,
 
   content::WebContents* web_contents() { return web_contents_; }
   Profile* profile() { return profile_; }
-  content::DevToolsClientHost* frontend_host() { return frontend_host_.get(); }
 
   // Takes ownership over the |delegate|.
   void SetDelegate(Delegate* delegate);
@@ -74,16 +74,23 @@ class DevToolsUIBindings : public content::NotificationObserver,
                           const base::Value* arg2,
                           const base::Value* arg3);
  private:
-  // content::NotificationObserver:
+  // content::NotificationObserver overrides.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
-  // content::DevToolsFrontendHostDelegate override:
+  // content::DevToolsFrontendHost::Delegate implementation.
+  virtual void HandleMessageFromDevToolsFrontend(
+      const std::string& message) OVERRIDE;
+  virtual void HandleMessageFromDevToolsFrontendToBackend(
+      const std::string& message) OVERRIDE;
+
+  // content::DevToolsClientHost implementation.
+  virtual void DispatchOnInspectorFrontend(const std::string& message) OVERRIDE;
   virtual void InspectedContentsClosing() OVERRIDE;
-  virtual void DispatchOnEmbedder(const std::string& message) OVERRIDE;
+  virtual void ReplacedWithAnotherClient() OVERRIDE;
 
-  // DevToolsEmbedderMessageDispatcher::Delegate overrides:
+  // DevToolsEmbedderMessageDispatcher::Delegate implementation.
   virtual void ActivateWindow() OVERRIDE;
   virtual void CloseWindow() OVERRIDE;
   virtual void SetInspectedPageBounds(const gfx::Rect& rect) OVERRIDE;
@@ -163,7 +170,7 @@ class DevToolsUIBindings : public content::NotificationObserver,
   content::WebContents* web_contents_;
   scoped_ptr<Delegate> delegate_;
   content::NotificationRegistrar registrar_;
-  scoped_ptr<content::DevToolsClientHost> frontend_host_;
+  scoped_ptr<content::DevToolsFrontendHost> frontend_host_;
   scoped_ptr<DevToolsFileHelper> file_helper_;
   scoped_refptr<DevToolsFileSystemIndexer> file_system_indexer_;
   typedef std::map<
diff --git a/chrome/browser/devtools/devtools_window.cc b/chrome/browser/devtools/devtools_window.cc
index 1a6962f..0dd6dbb 100644
--- a/chrome/browser/devtools/devtools_window.cc
+++ b/chrome/browser/devtools/devtools_window.cc
@@ -427,7 +427,7 @@ DevToolsWindow* DevToolsWindow::OpenDevToolsWindowForWorker(
     window = DevToolsWindow::CreateDevToolsWindowForWorker(profile);
     // Will disconnect the current client host if there is one.
     content::DevToolsManager::GetInstance()->RegisterDevToolsClientHostFor(
-        worker_agent, window->bindings_->frontend_host());
+        worker_agent, window->bindings_);
   }
   window->ScheduleShow(DevToolsToggleAction::Show());
   return window;
@@ -479,7 +479,7 @@ void DevToolsWindow::OpenExternalFrontend(
     window = Create(profile, DevToolsUI::GetProxyURL(frontend_url), NULL,
                     false, true, false, "");
     content::DevToolsManager::GetInstance()->RegisterDevToolsClientHostFor(
-        agent_host, window->bindings_->frontend_host());
+        agent_host, window->bindings_);
   }
   window->ScheduleShow(DevToolsToggleAction::Show());
 }
@@ -502,8 +502,7 @@ DevToolsWindow* DevToolsWindow::ToggleDevToolsWindow(
         base::UserMetricsAction("DevTools_InspectRenderer"));
     window = Create(
         profile, GURL(), inspected_rvh, false, false, true, settings);
-    manager->RegisterDevToolsClientHostFor(agent.get(),
-                                           window->bindings_->frontend_host());
+    manager->RegisterDevToolsClientHostFor(agent.get(), window->bindings_);
     do_open = true;
   }
 
@@ -799,8 +798,7 @@ DevToolsWindow* DevToolsWindow::FindDevToolsWindow(
   content::DevToolsManager* manager = content::DevToolsManager::GetInstance();
   for (DevToolsWindows::iterator it(instances->begin()); it != instances->end();
        ++it) {
-    if (manager->GetDevToolsAgentHostFor((*it)->bindings_->frontend_host()) ==
-        agent_host)
+    if (manager->GetDevToolsAgentHostFor((*it)->bindings_) == agent_host)
       return *it;
   }
   return NULL;
@@ -832,12 +830,12 @@ WebContents* DevToolsWindow::OpenURLFromTab(
 
   content::DevToolsManager* manager = content::DevToolsManager::GetInstance();
   scoped_refptr<DevToolsAgentHost> agent_host(
-      manager->GetDevToolsAgentHostFor(bindings_->frontend_host()));
+      manager->GetDevToolsAgentHostFor(bindings_));
   if (!agent_host.get())
     return NULL;
-  manager->ClientHostClosing(bindings_->frontend_host());
+  manager->ClientHostClosing(bindings_);
   manager->RegisterDevToolsClientHostFor(agent_host.get(),
-                                         bindings_->frontend_host());
+                                         bindings_);
 
   content::NavigationController::LoadURLParams load_url_params(params.url);
   main_web_contents_->GetController().LoadURLWithParams(load_url_params);
@@ -916,7 +914,7 @@ void DevToolsWindow::BeforeUnloadFired(WebContents* tab,
     // Docked devtools window closed directly.
     if (proceed) {
       content::DevToolsManager::GetInstance()->ClientHostClosing(
-          bindings_->frontend_host());
+          bindings_);
     }
     *proceed_to_fire_unload = proceed;
   } else {
diff --git a/chrome/browser/ui/webui/inspect_ui.cc b/chrome/browser/ui/webui/inspect_ui.cc
index 70401b1..dc203b6 100644
--- a/chrome/browser/ui/webui/inspect_ui.cc
+++ b/chrome/browser/ui/webui/inspect_ui.cc
@@ -295,7 +295,7 @@ void InspectUI::InspectBrowserWithCustomFrontend(
 
   // Engage remote debugging between front-end and agent host.
   content::DevToolsManager::GetInstance()->RegisterDevToolsClientHostFor(
-      agent_host, bindings->frontend_host());
+      agent_host, bindings);
 }
 
 void InspectUI::InspectDevices(Browser* browser) {
diff --git a/content/browser/devtools/devtools_frontend_host.cc b/content/browser/devtools/devtools_frontend_host.cc
deleted file mode 100644
index bfa623a..0000000
--- a/content/browser/devtools/devtools_frontend_host.cc
+++ /dev/null
@@ -1,96 +0,0 @@
-// Copyright (c) 2012 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/devtools_frontend_host.h"
-
-#include "content/browser/devtools/devtools_manager_impl.h"
-#include "content/browser/renderer_host/render_view_host_impl.h"
-#include "content/browser/web_contents/web_contents_impl.h"
-#include "content/common/devtools_messages.h"
-#include "content/public/browser/devtools_client_host.h"
-#include "content/public/browser/devtools_frontend_host_delegate.h"
-
-namespace content {
-
-// static
-DevToolsClientHost* DevToolsClientHost::CreateDevToolsFrontendHost(
-    WebContents* client_web_contents,
-    DevToolsFrontendHostDelegate* delegate) {
-  return new DevToolsFrontendHost(
-      static_cast<WebContentsImpl*>(client_web_contents), delegate);
-}
-
-// static
-void DevToolsClientHost::SetupDevToolsFrontendClient(
-    RenderViewHost* frontend_rvh) {
-  frontend_rvh->Send(new DevToolsMsg_SetupDevToolsClient(
-      frontend_rvh->GetRoutingID()));
-}
-
-DevToolsFrontendHost::DevToolsFrontendHost(
-    WebContentsImpl* web_contents,
-    DevToolsFrontendHostDelegate* delegate)
-    : WebContentsObserver(web_contents),
-      delegate_(delegate) {
-}
-
-DevToolsFrontendHost::~DevToolsFrontendHost() {
-  DevToolsManager::GetInstance()->ClientHostClosing(this);
-}
-
-void DevToolsFrontendHost::DispatchOnInspectorFrontend(
-    const std::string& message) {
-  if (!web_contents())
-    return;
-  RenderViewHostImpl* target_host =
-      static_cast<RenderViewHostImpl*>(web_contents()->GetRenderViewHost());
-  target_host->Send(new DevToolsClientMsg_DispatchOnInspectorFrontend(
-      target_host->GetRoutingID(),
-      message));
-}
-
-void DevToolsFrontendHost::InspectedContentsClosing() {
-  delegate_->InspectedContentsClosing();
-}
-
-void DevToolsFrontendHost::ReplacedWithAnotherClient() {
-}
-
-bool DevToolsFrontendHost::OnMessageReceived(
-    const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(DevToolsFrontendHost, message)
-    IPC_MESSAGE_HANDLER(DevToolsAgentMsg_DispatchOnInspectorBackend,
-                        OnDispatchOnInspectorBackend)
-    IPC_MESSAGE_HANDLER(DevToolsHostMsg_DispatchOnEmbedder,
-                        OnDispatchOnEmbedder)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void DevToolsFrontendHost::RenderProcessGone(
-    base::TerminationStatus status) {
-  switch(status) {
-    case base::TERMINATION_STATUS_ABNORMAL_TERMINATION:
-    case base::TERMINATION_STATUS_PROCESS_WAS_KILLED:
-    case base::TERMINATION_STATUS_PROCESS_CRASHED:
-      DevToolsManager::GetInstance()->ClientHostClosing(this);
-      break;
-    default:
-      break;
-  }
-}
-
-void DevToolsFrontendHost::OnDispatchOnInspectorBackend(
-    const std::string& message) {
-  DevToolsManagerImpl::GetInstance()->DispatchOnInspectorBackend(this, message);
-}
-
-void DevToolsFrontendHost::OnDispatchOnEmbedder(
-    const std::string& message) {
-  delegate_->DispatchOnEmbedder(message);
-}
-
-}  // namespace content
diff --git a/content/browser/devtools/devtools_frontend_host.h b/content/browser/devtools/devtools_frontend_host.h
deleted file mode 100644
index 469d162..0000000
--- a/content/browser/devtools/devtools_frontend_host.h
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright (c) 2012 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.
-
-#ifndef CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_H_
-#define CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_H_
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "content/public/browser/devtools_client_host.h"
-#include "content/public/browser/web_contents_observer.h"
-
-namespace content {
-
-class DevToolsFrontendHostDelegate;
-class WebContentsImpl;
-
-// This class handles messages from DevToolsClient and calls corresponding
-// methods on DevToolsFrontendHostDelegate which is implemented by the
-// embedder. This allows us to avoid exposing DevTools client messages through
-// the content public API.
-class DevToolsFrontendHost : public DevToolsClientHost,
-                             public WebContentsObserver {
- public:
-  DevToolsFrontendHost(WebContentsImpl* web_contents,
-                       DevToolsFrontendHostDelegate* delegate);
-
- private:
-  virtual ~DevToolsFrontendHost();
-
-  // DevToolsClientHost implementation.
-  virtual void DispatchOnInspectorFrontend(const std::string& message) OVERRIDE;
-  virtual void InspectedContentsClosing() OVERRIDE;
-  virtual void ReplacedWithAnotherClient() OVERRIDE;
-
-  // WebContentsObserver overrides.
-  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
-  virtual void RenderProcessGone(base::TerminationStatus status) OVERRIDE;
-
-  void OnDispatchOnInspectorBackend(const std::string& message);
-  void OnDispatchOnEmbedder(const std::string& message);
-
-  DevToolsFrontendHostDelegate* delegate_;
-  DISALLOW_COPY_AND_ASSIGN(DevToolsFrontendHost);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_H_
diff --git a/content/browser/devtools/devtools_frontend_host_impl.cc b/content/browser/devtools/devtools_frontend_host_impl.cc
new file mode 100644
index 0000000..9a81dfd
--- /dev/null
+++ b/content/browser/devtools/devtools_frontend_host_impl.cc
@@ -0,0 +1,66 @@
+// 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/devtools_frontend_host_impl.h"
+
+#include "content/common/devtools_messages.h"
+#include "content/public/browser/navigation_entry.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/web_contents.h"
+
+namespace content {
+
+// static
+DevToolsFrontendHost* DevToolsFrontendHost::Create(
+    RenderViewHost* frontend_rvh,
+    DevToolsFrontendHost::Delegate* delegate) {
+  return new DevToolsFrontendHostImpl(frontend_rvh, delegate);
+}
+
+DevToolsFrontendHostImpl::DevToolsFrontendHostImpl(
+    RenderViewHost* frontend_rvh,
+    DevToolsFrontendHost::Delegate* delegate)
+    : WebContentsObserver(WebContents::FromRenderViewHost(frontend_rvh)),
+      delegate_(delegate) {
+  frontend_rvh->Send(new DevToolsMsg_SetupDevToolsClient(
+      frontend_rvh->GetRoutingID()));
+}
+
+DevToolsFrontendHostImpl::~DevToolsFrontendHostImpl() {
+}
+
+void DevToolsFrontendHostImpl::DispatchOnDevToolsFrontend(
+    const std::string& message) {
+  if (!web_contents())
+    return;
+  RenderViewHost* target_host = web_contents()->GetRenderViewHost();
+  target_host->Send(new DevToolsClientMsg_DispatchOnInspectorFrontend(
+      target_host->GetRoutingID(),
+      message));
+}
+
+bool DevToolsFrontendHostImpl::OnMessageReceived(
+    const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(DevToolsFrontendHostImpl, message)
+    IPC_MESSAGE_HANDLER(DevToolsAgentMsg_DispatchOnInspectorBackend,
+                        OnDispatchOnInspectorBackend)
+    IPC_MESSAGE_HANDLER(DevToolsHostMsg_DispatchOnEmbedder,
+                        OnDispatchOnEmbedder)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void DevToolsFrontendHostImpl::OnDispatchOnInspectorBackend(
+    const std::string& message) {
+  delegate_->HandleMessageFromDevToolsFrontendToBackend(message);
+}
+
+void DevToolsFrontendHostImpl::OnDispatchOnEmbedder(
+    const std::string& message) {
+  delegate_->HandleMessageFromDevToolsFrontend(message);
+}
+
+}  // namespace content
diff --git a/content/browser/devtools/devtools_frontend_host_impl.h b/content/browser/devtools/devtools_frontend_host_impl.h
new file mode 100644
index 0000000..b6bb79b
--- /dev/null
+++ b/content/browser/devtools/devtools_frontend_host_impl.h
@@ -0,0 +1,36 @@
+// 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.
+
+#ifndef CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_IMPL_H_
+#define CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_IMPL_H_
+
+#include "content/public/browser/devtools_frontend_host.h"
+#include "content/public/browser/web_contents_observer.h"
+
+namespace content {
+
+class DevToolsFrontendHostImpl : public DevToolsFrontendHost,
+                                 public WebContentsObserver {
+ public:
+  DevToolsFrontendHostImpl(RenderViewHost* frontend_rvh,
+                           DevToolsFrontendHost::Delegate* delegate);
+  virtual ~DevToolsFrontendHostImpl();
+
+  // DevToolsFrontendHost implementation.
+  virtual void DispatchOnDevToolsFrontend(const std::string& message) OVERRIDE;
+
+ private:
+  // WebContentsObserver overrides.
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  void OnDispatchOnInspectorBackend(const std::string& message);
+  void OnDispatchOnEmbedder(const std::string& message);
+
+  DevToolsFrontendHost::Delegate* delegate_;
+  DISALLOW_COPY_AND_ASSIGN(DevToolsFrontendHostImpl);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_FRONTEND_HOST_IMPL_H_
diff --git a/content/content_browser.gypi b/content/content_browser.gypi
index b1477e4..452985e 100644
--- a/content/content_browser.gypi
+++ b/content/content_browser.gypi
@@ -100,7 +100,7 @@
       'public/browser/devtools_external_agent_proxy.h',
       'public/browser/devtools_external_agent_proxy_delegate.h',
       'public/browser/download_danger_type.h',
-      'public/browser/devtools_frontend_host_delegate.h',
+      'public/browser/devtools_frontend_host.h',
       'public/browser/devtools_http_handler.h',
       'public/browser/devtools_http_handler_delegate.h',
       'public/browser/devtools_manager.h',
@@ -422,8 +422,8 @@
       'browser/devtools/devtools_agent_host_impl.h',
       'browser/devtools/devtools_browser_target.cc',
       'browser/devtools/devtools_browser_target.h',
-      'browser/devtools/devtools_frontend_host.cc',
-      'browser/devtools/devtools_frontend_host.h',
+      'browser/devtools/devtools_frontend_host_impl.cc',
+      'browser/devtools/devtools_frontend_host_impl.h',
       'browser/devtools/devtools_http_handler_impl.cc',
       'browser/devtools/devtools_http_handler_impl.h',
       'browser/devtools/devtools_manager_impl.cc',
diff --git a/content/public/browser/devtools_client_host.h b/content/public/browser/devtools_client_host.h
index fe76d3c..67b7003 100644
--- a/content/public/browser/devtools_client_host.h
+++ b/content/public/browser/devtools_client_host.h
@@ -38,15 +38,6 @@ class CONTENT_EXPORT DevToolsClientHost {
   // Called to notify client that it has been kicked out by some other client
   // with greater priority.
   virtual void ReplacedWithAnotherClient() = 0;
-
-  // Creates a DevToolsClientHost for a WebContents containing the default
-  // DevTools frontend implementation.
-  static DevToolsClientHost* CreateDevToolsFrontendHost(
-      WebContents* client_web_contents,
-      DevToolsFrontendHostDelegate* delegate);
-
-  // Sets up DevToolsClient on the corresponding RenderView.
-  static void SetupDevToolsFrontendClient(RenderViewHost* frontend_rvh);
 };
 
 }  // namespace content
diff --git a/content/public/browser/devtools_frontend_host.h b/content/public/browser/devtools_frontend_host.h
new file mode 100644
index 0000000..ac79df2
--- /dev/null
+++ b/content/public/browser/devtools_frontend_host.h
@@ -0,0 +1,53 @@
+// 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.
+
+#ifndef CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_H_
+#define CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_H_
+
+#include <string>
+
+#include "content/common/content_export.h"
+
+namespace content {
+
+class RenderViewHost;
+
+// This class dispatches messages between DevTools frontend and Delegate
+// which is implemented by the embedder.
+// This allows us to avoid exposing DevTools frontend messages through
+// the content public API.
+class DevToolsFrontendHost {
+ public:
+  // Delegate actually handles messages from frontend.
+  class Delegate {
+   public:
+    virtual ~Delegate() {}
+
+    // Message is coming from frontend to the embedder.
+    virtual void HandleMessageFromDevToolsFrontend(
+        const std::string& message) = 0;
+
+    // Message is coming from frontend to the backend.
+    // TODO(dgozman): remove this by making one of the possible messages
+    // passed via the method above.
+    virtual void HandleMessageFromDevToolsFrontendToBackend(
+        const std::string& message) = 0;
+  };
+
+  // Creates a new DevToolsFrontendHost for RenderViewHost where DevTools
+  // frontend is loaded.
+  CONTENT_EXPORT static DevToolsFrontendHost* Create(
+      RenderViewHost* frontend_rvh, Delegate* delegate);
+
+  CONTENT_EXPORT virtual ~DevToolsFrontendHost() {}
+
+  // Dispatches message from embedder/backend to frontend.
+  // TODO(dgozman): remove and make embedder to take care of this.
+  CONTENT_EXPORT virtual void DispatchOnDevToolsFrontend(
+      const std::string& message) = 0;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_H_
diff --git a/content/public/browser/devtools_frontend_host_delegate.h b/content/public/browser/devtools_frontend_host_delegate.h
deleted file mode 100644
index 1d41bef..0000000
--- a/content/public/browser/devtools_frontend_host_delegate.h
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright (c) 2012 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.
-
-#ifndef CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_DELEGATE_H_
-#define CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_DELEGATE_H_
-
-#include <string>
-
-namespace content {
-
-// Clients that want to use default DevTools front-end implementation should
-// implement this interface to provide access to the embedding browser from
-// the front-end.
-class DevToolsFrontendHostDelegate {
- public:
-  virtual ~DevToolsFrontendHostDelegate() {}
-
-  // Dispatch the message from the frontend to the frontend host.
-  virtual void DispatchOnEmbedder(const std::string& message) = 0;
-
-  // This method is called when the contents inspected by this devtools frontend
-  // is closing.
-  virtual void InspectedContentsClosing() = 0;
-};
-
-}  // namespace content
-
-#endif  // CONTENT_PUBLIC_BROWSER_DEVTOOLS_FRONTEND_HOST_DELEGATE_H_
diff --git a/content/shell/browser/shell_devtools_frontend.cc b/content/shell/browser/shell_devtools_frontend.cc
index e64685d..fe30edd 100644
--- a/content/shell/browser/shell_devtools_frontend.cc
+++ b/content/shell/browser/shell_devtools_frontend.cc
@@ -106,8 +106,6 @@ ShellDevToolsFrontend::ShellDevToolsFrontend(Shell* frontend_shell,
     : WebContentsObserver(frontend_shell->web_contents()),
       frontend_shell_(frontend_shell),
       agent_host_(agent_host) {
-  frontend_host_.reset(
-      DevToolsClientHost::CreateDevToolsFrontendHost(web_contents(), this));
 }
 
 ShellDevToolsFrontend::~ShellDevToolsFrontend() {
@@ -115,11 +113,11 @@ ShellDevToolsFrontend::~ShellDevToolsFrontend() {
 
 void ShellDevToolsFrontend::RenderViewCreated(
     RenderViewHost* render_view_host) {
-  DevToolsClientHost::SetupDevToolsFrontendClient(
-      web_contents()->GetRenderViewHost());
-  DevToolsManager* manager = DevToolsManager::GetInstance();
-  manager->RegisterDevToolsClientHostFor(agent_host_.get(),
-                                         frontend_host_.get());
+  if (!frontend_host_) {
+    frontend_host_.reset(DevToolsFrontendHost::Create(render_view_host, this));
+    DevToolsManager::GetInstance()->RegisterDevToolsClientHostFor(
+        agent_host_.get(), this);
+  }
 }
 
 void ShellDevToolsFrontend::DocumentOnLoadCompletedInMainFrame() {
@@ -128,7 +126,7 @@ void ShellDevToolsFrontend::DocumentOnLoadCompletedInMainFrame() {
 }
 
 void ShellDevToolsFrontend::WebContentsDestroyed() {
-  DevToolsManager::GetInstance()->ClientHostClosing(frontend_host_.get());
+  DevToolsManager::GetInstance()->ClientHostClosing(this);
   delete this;
 }
 
@@ -137,6 +135,18 @@ void ShellDevToolsFrontend::RenderProcessGone(base::TerminationStatus status) {
     WebKitTestController::Get()->DevToolsProcessCrashed();
 }
 
+void ShellDevToolsFrontend::HandleMessageFromDevToolsFrontendToBackend(
+    const std::string& message) {
+  DevToolsManager::GetInstance()->DispatchOnInspectorBackend(
+      this, message);
+}
+
+void ShellDevToolsFrontend::DispatchOnInspectorFrontend(
+    const std::string& message) {
+  if (frontend_host_)
+    frontend_host_->DispatchOnDevToolsFrontend(message);
+}
+
 void ShellDevToolsFrontend::InspectedContentsClosing() {
   frontend_shell_->Close();
 }
diff --git a/content/shell/browser/shell_devtools_frontend.h b/content/shell/browser/shell_devtools_frontend.h
index f08aa24..381ff22 100644
--- a/content/shell/browser/shell_devtools_frontend.h
+++ b/content/shell/browser/shell_devtools_frontend.h
@@ -11,7 +11,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "content/public/browser/devtools_agent_host.h"
 #include "content/public/browser/devtools_client_host.h"
-#include "content/public/browser/devtools_frontend_host_delegate.h"
+#include "content/public/browser/devtools_frontend_host.h"
 #include "content/public/browser/web_contents_observer.h"
 
 namespace content {
@@ -24,7 +24,8 @@ class Shell;
 class WebContents;
 
 class ShellDevToolsFrontend : public WebContentsObserver,
-                              public DevToolsFrontendHostDelegate {
+                              public DevToolsFrontendHost::Delegate,
+                              public DevToolsClientHost {
  public:
   static ShellDevToolsFrontend* Show(WebContents* inspected_contents);
   static ShellDevToolsFrontend* Show(WebContents* inspected_contents,
@@ -47,14 +48,20 @@ class ShellDevToolsFrontend : public WebContentsObserver,
   virtual void WebContentsDestroyed() OVERRIDE;
   virtual void RenderProcessGone(base::TerminationStatus status) OVERRIDE;
 
-  // DevToolsFrontendHostDelegate implementation
-  virtual void DispatchOnEmbedder(const std::string& message) OVERRIDE {}
+  // content::DevToolsFrontendHost::Delegate implementation.
+  virtual void HandleMessageFromDevToolsFrontend(
+      const std::string& message) OVERRIDE {}
+  virtual void HandleMessageFromDevToolsFrontendToBackend(
+      const std::string& message) OVERRIDE;
 
+  // content::DevToolsClientHost implementation.
+  virtual void DispatchOnInspectorFrontend(const std::string& message) OVERRIDE;
   virtual void InspectedContentsClosing() OVERRIDE;
+  virtual void ReplacedWithAnotherClient() OVERRIDE {}
 
   Shell* frontend_shell_;
   scoped_refptr<DevToolsAgentHost> agent_host_;
-  scoped_ptr<DevToolsClientHost> frontend_host_;
+  scoped_ptr<DevToolsFrontendHost> frontend_host_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellDevToolsFrontend);
 };