Remove ack bundling mode.

gfe-relnote: Deprecate gfe2_reloadable_flag_quic_deprecate_ack_bundling_mode.
PiperOrigin-RevId: 253856112
Change-Id: Iaa62b97be5904743c56c5b48b230446a9c4bd870
diff --git a/quic/core/http/end_to_end_test.cc b/quic/core/http/end_to_end_test.cc
index fa60c96..a64b289 100644
--- a/quic/core/http/end_to_end_test.cc
+++ b/quic/core/http/end_to_end_test.cc
@@ -3612,8 +3612,7 @@
       QuicConnectionPeer::GetHelper(client_connection)->GetRandomGenerator();
   QuicMemSliceStorage storage(nullptr, 0, nullptr, 0);
   {
-    QuicConnection::ScopedPacketFlusher flusher(
-        client_session->connection(), QuicConnection::SEND_ACK_IF_PENDING);
+    QuicConnection::ScopedPacketFlusher flusher(client_session->connection());
     // Verify the largest message gets successfully sent.
     EXPECT_EQ(
         MessageResult(MESSAGE_STATUS_SUCCESS, 1),
diff --git a/quic/core/http/quic_send_control_stream.cc b/quic/core/http/quic_send_control_stream.cc
index 7003b21..8002b0c 100644
--- a/quic/core/http/quic_send_control_stream.cc
+++ b/quic/core/http/quic_send_control_stream.cc
@@ -25,8 +25,7 @@
 void QuicSendControlStream::SendSettingsFrame(const SettingsFrame& settings) {
   DCHECK(!settings_sent_);
 
-  QuicConnection::ScopedPacketFlusher flusher(
-      session()->connection(), QuicConnection::SEND_ACK_IF_PENDING);
+  QuicConnection::ScopedPacketFlusher flusher(session()->connection());
   // Send the stream type on so the peer knows about this stream.
   char data[sizeof(kControlStream)];
   QuicDataWriter writer(QUIC_ARRAYSIZE(data), data);
diff --git a/quic/core/http/quic_spdy_client_stream.cc b/quic/core/http/quic_spdy_client_stream.cc
index 2903b30..5cbb79d 100644
--- a/quic/core/http/quic_spdy_client_stream.cc
+++ b/quic/core/http/quic_spdy_client_stream.cc
@@ -142,8 +142,7 @@
 size_t QuicSpdyClientStream::SendRequest(SpdyHeaderBlock headers,
                                          QuicStringPiece body,
                                          bool fin) {
-  QuicConnection::ScopedPacketFlusher flusher(
-      session_->connection(), QuicConnection::SEND_ACK_IF_QUEUED);
+  QuicConnection::ScopedPacketFlusher flusher(session_->connection());
   bool send_fin_with_headers = fin && body.empty();
   size_t bytes_sent = body.size();
   header_bytes_written_ =
diff --git a/quic/core/http/quic_spdy_stream.cc b/quic/core/http/quic_spdy_stream.cc
index bac53ce..fa43d54 100644
--- a/quic/core/http/quic_spdy_stream.cc
+++ b/quic/core/http/quic_spdy_stream.cc
@@ -218,8 +218,7 @@
     SpdyHeaderBlock header_block,
     bool fin,
     QuicReferenceCountedPointer<QuicAckListenerInterface> ack_listener) {
-  QuicConnection::ScopedPacketFlusher flusher(
-      spdy_session_->connection(), QuicConnection::SEND_ACK_IF_PENDING);
+  QuicConnection::ScopedPacketFlusher flusher(spdy_session_->connection());
   // Send stream type for server push stream
   if (VersionHasStreamType(session()->connection()->transport_version()) &&
       type() == WRITE_UNIDIRECTIONAL && send_buffer().stream_offset() == 0) {
@@ -256,8 +255,7 @@
     WriteOrBufferData(data, fin, nullptr);
     return;
   }
-  QuicConnection::ScopedPacketFlusher flusher(
-      spdy_session_->connection(), QuicConnection::SEND_ACK_IF_PENDING);
+  QuicConnection::ScopedPacketFlusher flusher(spdy_session_->connection());
 
   // Write frame header.
   std::unique_ptr<char[]> buffer;
@@ -344,8 +342,7 @@
     return {0, false};
   }
 
-  QuicConnection::ScopedPacketFlusher flusher(
-      spdy_session_->connection(), QuicConnection::SEND_ACK_IF_PENDING);
+  QuicConnection::ScopedPacketFlusher flusher(spdy_session_->connection());
 
   // Write frame header.
   struct iovec header_iov = {static_cast<void*>(buffer.get()), header_length};