Remove redundant stream finding code when STOP_SENDING frame is received.

QuicSession::OnStopSending() already finds the stream and does staticness checks. We can simplify QuicSession::SendRstStreamInner() by moving the stream book keeping to OnStopSending().

gfe-relnote: protected by disabled v99 flag.
PiperOrigin-RevId: 278745064
Change-Id: I3734cff264fdadd58d3dfe50b418fd4c76bd19ce

quic/core/quic_session.cc

diff --git a/quic/core/quic_session.cc b/quic/core/quic_session.cc
index c16b723..2761e61 100644
--- a/quic/core/quic_session.cc
+++ b/quic/core/quic_session.cc
@@ -272,6 +272,8 @@
       static_cast<quic::QuicRstStreamErrorCode>(frame.application_error_code),
       stream->stream_bytes_written(),
       /*close_write_side_only=*/true);
+  stream->set_rst_sent(true);
+  stream->CloseWriteSide();
 }
 
 void QuicSession::PendingStreamOnRstStream(const QuicRstStreamFrame& frame) {
@@ -715,26 +717,6 @@
 
   if (!close_write_side_only) {
     CloseStreamInner(id, true);
-    return;
-  }
-  DCHECK(VersionHasIetfQuicFrames(transport_version()));
-
-  StreamMap::iterator it = stream_map_.find(id);
-  if (it != stream_map_.end()) {
-    if (it->second->is_static()) {
-      QUIC_DVLOG(1) << ENDPOINT
-                    << "Try to send rst for a static stream, id: " << id
-                    << " Closing connection";
-      connection()->CloseConnection(
-          QUIC_INVALID_STREAM_ID, "Sending rst for a static stream",
-          ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET);
-      return;
-    }
-    QuicStream* stream = it->second.get();
-    if (stream) {
-      stream->set_rst_sent(true);
-      stream->CloseWriteSide();
-    }
   }
 }
 

quic/core/quic_session.h

diff --git a/quic/core/quic_session.h b/quic/core/quic_session.h
index 6a6a4b2..c4f2d98 100644
--- a/quic/core/quic_session.h
+++ b/quic/core/quic_session.h
@@ -209,7 +209,9 @@
   // the peer. Returns true if |frame| is consumed, false otherwise.
   virtual bool WriteControlFrame(const QuicFrame& frame);
 
-  // Called by streams when they want to close the stream in both directions.
+  // Close the stream in both directions.
+  // TODO(renjietang): rename this method as it sends both RST_STREAM and
+  // STOP_SENDING in IETF QUIC.
   virtual void SendRstStream(QuicStreamId id,
                              QuicRstStreamErrorCode error,
                              QuicStreamOffset bytes_written);

quic/core/quic_stream_test.cc

diff --git a/quic/core/quic_stream_test.cc b/quic/core/quic_stream_test.cc
index 74fbcf2..c82b4d0 100644
--- a/quic/core/quic_stream_test.cc
+++ b/quic/core/quic_stream_test.cc
@@ -1577,27 +1577,6 @@
   }
 }
 
-// Test that receiving a STOP_SENDING just closes the write side of the stream.
-// If not V99, the test is a noop (no STOP_SENDING in Google QUIC).
-TEST_P(QuicStreamTest, OnStopSendingReadOrReadWrite) {
-  Initialize();
-  if (!VersionHasIetfQuicFrames(connection_->transport_version())) {
-    return;
-  }
-
-  EXPECT_FALSE(stream_->write_side_closed());
-  EXPECT_FALSE(QuicStreamPeer::read_side_closed(stream_));
-
-  // Simulate receipt of a STOP_SENDING.
-  stream_->OnStopSending(123);
-
-  // Should close just the read side.
-  EXPECT_FALSE(QuicStreamPeer::read_side_closed(stream_));
-  // TODO(b/142425843): Currently no action is taken upon receiving stop
-  // sending. Need to figure out what to do and turn on this expectation.
-  // EXPECT_TRUE(stream_->write_side_closed());
-}
-
 // SendOnlyRstStream must only send a RESET_STREAM (no bundled STOP_SENDING).
 TEST_P(QuicStreamTest, SendOnlyRstStream) {
   Initialize();
@@ -1615,10 +1594,6 @@
                                       QUIC_BAD_APPLICATION_PAYLOAD,
                                       stream_->stream_bytes_written(),
                                       /*close_write_side_only=*/true);
-
-  // ResetStreamOnly should just close the write side.
-  EXPECT_FALSE(QuicStreamPeer::read_side_closed(stream_));
-  EXPECT_TRUE(stream_->write_side_closed());
 }
 
 TEST_P(QuicStreamTest, WindowUpdateForReadOnlyStream) {