Revert r113405, since it appears to be causing a crash and a hang.

net/spdy/spdy_session.h

Index: net/spdy/spdy_session.h
diff --git a/net/spdy/spdy_session.h b/net/spdy/spdy_session.h
index 2fc6621798ce157253e8db3f00a79e20ecf520eb..245fdd68870c0043c830e6dbf4733f95e5d8d10b 100644
--- a/net/spdy/spdy_session.h
+++ b/net/spdy/spdy_session.h
@@ -46,8 +46,7 @@ class SpdyStream;
 class SSLInfo;
 
 class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
-                               public spdy::BufferedSpdyFramerVisitorInterface,
-                               public LayeredPool {
+                               public spdy::BufferedSpdyFramerVisitorInterface {
  public:
   // Create a new SpdySession.
   // |host_port_proxy_pair| is the host/port that this session connects to, and
@@ -237,9 +236,6 @@ class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
   int GetPeerAddress(AddressList* address) const;
   int GetLocalAddress(IPEndPoint* address) const;
 
-  // LayeredPool implementation.
-  virtual bool CloseOneIdleConnection() OVERRIDE;
-
  private:
   friend class base::RefCounted<SpdySession>;