DevTools: retain DTAH in all the targets to match their life time.

content/browser/devtools/devtools_http_handler.h

Index: content/browser/devtools/devtools_http_handler.h
diff --git a/content/browser/devtools/devtools_http_handler.h b/content/browser/devtools/devtools_http_handler.h
index 657abb4f1a72d8017817e7b1eb6a002e544b3bc4..5989da0188106475a4ff5718946e27b4a74a5a56 100644
--- a/content/browser/devtools/devtools_http_handler.h
+++ b/content/browser/devtools/devtools_http_handler.h
@@ -85,9 +85,6 @@ class DevToolsHttpHandler {
                      DevToolsSocketFactory* socket_factory,
                      std::unique_ptr<net::IPEndPoint> ip_address);
 
-  scoped_refptr<DevToolsAgentHost> GetAgentHost(
-      const std::string& target_id);
-
   void SendJson(int connection_id,
                 net::HttpStatusCode status_code,
                 base::Value* value,
@@ -121,9 +118,6 @@ class DevToolsHttpHandler {
   ConnectionToClientMap connection_to_client_;
   DevToolsManagerDelegate* delegate_;
   DevToolsSocketFactory* socket_factory_;
-  using DescriptorMap =
-      std::map<std::string, scoped_refptr<DevToolsAgentHost>>;
-  DescriptorMap agent_host_map_;
   base::WeakPtrFactory<DevToolsHttpHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DevToolsHttpHandler);