[DevTools] Expose DevToolsAgentHost for OOPIF, display it in chrome://inspect.

content/browser/devtools/render_frame_devtools_agent_host.h

Index: content/browser/devtools/render_frame_devtools_agent_host.h
diff --git a/content/browser/devtools/render_frame_devtools_agent_host.h b/content/browser/devtools/render_frame_devtools_agent_host.h
index 3f4d23b5ca40221ad1336810ac738c22ae51c359..ca6d15378c69e7dff7807cf044bdedb05cdac1fa 100644
--- a/content/browser/devtools/render_frame_devtools_agent_host.h
+++ b/content/browser/devtools/render_frame_devtools_agent_host.h
@@ -47,6 +47,9 @@ class CONTENT_EXPORT RenderFrameDevToolsAgentHost
       private WebContentsObserver,
       public NotificationObserver {
  public:
+  static void AddAllAgentHosts(
+      std::vector<scoped_refptr<DevToolsAgentHost>>* result);
+
   static void OnCancelPendingNavigation(RenderFrameHost* pending,
                                         RenderFrameHost* current);
 
@@ -71,6 +74,11 @@ class CONTENT_EXPORT RenderFrameDevToolsAgentHost
   explicit RenderFrameDevToolsAgentHost(RenderFrameHost*);
   ~RenderFrameDevToolsAgentHost() override;
 
+  static scoped_refptr<DevToolsAgentHost> GetOrCreateFor(RenderFrameHost* host);
+  static void AppendAgentHostForFrameIfApplicable(
+      std::vector<scoped_refptr<DevToolsAgentHost>>* result,
+      RenderFrameHost* host);
+
   // IPCDevToolsAgentHost overrides.
   void DispatchProtocolMessage(const std::string& message) override;
   void SendMessageToAgent(IPC::Message* msg) override;
@@ -117,6 +125,8 @@ class CONTENT_EXPORT RenderFrameDevToolsAgentHost
   void InnerOnClientAttached();
   void InnerClientDetachedFromRenderer();
 
+  bool IsChildFrame();
+
   RenderFrameHostImpl* render_frame_host_;
   scoped_ptr<devtools::dom::DOMHandler> dom_handler_;
   scoped_ptr<devtools::input::InputHandler> input_handler_;