Remove IETF QUIC Application Close frame, replace with Connection Close

This CL removes the IETF QUIC Application Close frame and replaces it with the Connection Close frame.  QuicConnectionCloseFrame::close_type indicates whether the frame is a Google QUIC Connection Close, IETF QUIC Connection Close/Transport or IETF QUIC Connection Close/Application.

The QuicFramer::...ApplicationCloseFrame... methods are removed.

gfe-relnote: N/A affects only IETF-QUIC/V99 code. Application Close was IETF-QUIC only.
PiperOrigin-RevId: 242881293
Change-Id: I783cbf4e5f27d2e5abe3e8b518006de03c815e1a
diff --git a/quic/test_tools/simple_quic_framer.cc b/quic/test_tools/simple_quic_framer.cc
index c02ed15..7b6e753 100644
--- a/quic/test_tools/simple_quic_framer.cc
+++ b/quic/test_tools/simple_quic_framer.cc
@@ -125,8 +125,7 @@
     return true;
   }
 
-  bool OnApplicationCloseFrame(
-      const QuicApplicationCloseFrame& frame) override {
+  bool OnApplicationCloseFrame(const QuicConnectionCloseFrame& frame) override {
     application_close_frames_.push_back(frame);
     return true;
   }
@@ -208,7 +207,7 @@
   const std::vector<QuicConnectionCloseFrame>& connection_close_frames() const {
     return connection_close_frames_;
   }
-  const std::vector<QuicApplicationCloseFrame>& application_close_frames()
+  const std::vector<QuicConnectionCloseFrame>& application_close_frames()
       const {
     return application_close_frames_;
   }
@@ -273,7 +272,7 @@
   std::vector<QuicStreamIdBlockedFrame> stream_id_blocked_frames_;
   std::vector<QuicMaxStreamIdFrame> max_stream_id_frames_;
   std::vector<QuicConnectionCloseFrame> connection_close_frames_;
-  std::vector<QuicApplicationCloseFrame> application_close_frames_;
+  std::vector<QuicConnectionCloseFrame> application_close_frames_;
   std::vector<QuicStopSendingFrame> stop_sending_frames_;
   std::vector<QuicPathChallengeFrame> path_challenge_frames_;
   std::vector<QuicPathResponseFrame> path_response_frames_;