Remove QuicSession::num_active_request() and allow subclasses to account the number of request individually.

gfe-relnote: n/a - code refactor.
PiperOrigin-RevId: 237508966
Change-Id: Id33ba212a4cfbd73f07264d5f6bcf95908fe772b
diff --git a/quic/core/http/quic_spdy_session.h b/quic/core/http/quic_spdy_session.h
index 00f241e..93067fa 100644
--- a/quic/core/http/quic_spdy_session.h
+++ b/quic/core/http/quic_spdy_session.h
@@ -159,6 +159,9 @@
     max_inbound_header_list_size_ = max_inbound_header_list_size;
   }
 
+  // Returns true if the session has active request streams.
+  bool HasActiveRequestStreams() const;
+
  protected:
   // Override CreateIncomingStream(), CreateOutgoingBidirectionalStream() and
   // CreateOutgoingUnidirectionalStream() with QuicSpdyStream return type to