Remove PathCloseFrame, QuicPathId, DefaultPathId and InvalidPathId.

net/quic/core/frames/quic_frame.h

Index: net/quic/core/frames/quic_frame.h
diff --git a/net/quic/core/frames/quic_frame.h b/net/quic/core/frames/quic_frame.h
index 3ebe1cfc3de7d06cfefed3ab4b6082f90ecff3c8..fce45b5fda376cc7eb1eedd2086b19f9c513e2db 100644
--- a/net/quic/core/frames/quic_frame.h
+++ b/net/quic/core/frames/quic_frame.h
@@ -15,7 +15,6 @@
 #include "net/quic/core/frames/quic_goaway_frame.h"
 #include "net/quic/core/frames/quic_mtu_discovery_frame.h"
 #include "net/quic/core/frames/quic_padding_frame.h"
-#include "net/quic/core/frames/quic_path_close_frame.h"
 #include "net/quic/core/frames/quic_ping_frame.h"
 #include "net/quic/core/frames/quic_rst_stream_frame.h"
 #include "net/quic/core/frames/quic_stop_waiting_frame.h"
@@ -40,7 +39,6 @@ struct QUIC_EXPORT_PRIVATE QuicFrame {
   explicit QuicFrame(QuicGoAwayFrame* frame);
   explicit QuicFrame(QuicWindowUpdateFrame* frame);
   explicit QuicFrame(QuicBlockedFrame* frame);
-  explicit QuicFrame(QuicPathCloseFrame* frame);
 
   QUIC_EXPORT_PRIVATE friend std::ostream& operator<<(std::ostream& os,
                                                       const QuicFrame& frame);
@@ -61,7 +59,6 @@ struct QUIC_EXPORT_PRIVATE QuicFrame {
     QuicGoAwayFrame* goaway_frame;
     QuicWindowUpdateFrame* window_update_frame;
     QuicBlockedFrame* blocked_frame;
-    QuicPathCloseFrame* path_close_frame;
   };
 };
 // QuicFrameType consumes 8 bytes with padding.