Reverting again ... More crashes, and the instrumentation did not appear to help

net/http/http_proxy_client_socket_pool.h

Index: net/http/http_proxy_client_socket_pool.h
===================================================================
--- net/http/http_proxy_client_socket_pool.h	(revision 131144)
+++ net/http/http_proxy_client_socket_pool.h	(working copy)
@@ -170,9 +170,7 @@
   DISALLOW_COPY_AND_ASSIGN(HttpProxyConnectJob);
 };
 
-class NET_EXPORT_PRIVATE HttpProxyClientSocketPool
-    : public ClientSocketPool,
-      public LayeredPool {
+class NET_EXPORT_PRIVATE HttpProxyClientSocketPool : public ClientSocketPool {
  public:
   HttpProxyClientSocketPool(
       int max_sockets,
@@ -207,8 +205,6 @@
 
   virtual void Flush() OVERRIDE;
 
-  virtual bool IsStalled() const OVERRIDE;
-
   virtual void CloseIdleSockets() OVERRIDE;
 
   virtual int IdleSocketCount() const OVERRIDE;
@@ -220,10 +216,6 @@
       const std::string& group_name,
       const ClientSocketHandle* handle) const OVERRIDE;
 
-  virtual void AddLayeredPool(LayeredPool* layered_pool) OVERRIDE;
-
-  virtual void RemoveLayeredPool(LayeredPool* layered_pool) OVERRIDE;
-
   virtual base::DictionaryValue* GetInfoAsValue(
       const std::string& name,
       const std::string& type,
@@ -233,9 +225,6 @@
 
   virtual ClientSocketPoolHistograms* histograms() const OVERRIDE;
 
-  // LayeredPool implementation.
-  virtual bool CloseOneIdleConnection() OVERRIDE;
-
  private:
   typedef ClientSocketPoolBase<HttpProxySocketParams> PoolBase;