Clean up QuicStreamSendBuffer.

Remove unused variable, set member variable values inline instead of the constructor, clean up includes.

PiperOrigin-RevId: 757892389
diff --git a/quiche/quic/core/quic_stream_send_buffer.cc b/quiche/quic/core/quic_stream_send_buffer.cc
index 0d5703a..b0dd4d8 100644
--- a/quiche/quic/core/quic_stream_send_buffer.cc
+++ b/quiche/quic/core/quic_stream_send_buffer.cc
@@ -5,16 +5,21 @@
 #include "quiche/quic/core/quic_stream_send_buffer.h"
 
 #include <algorithm>
+#include <cstddef>
 #include <utility>
 
+#include "absl/strings/string_view.h"
+#include "absl/types/span.h"
 #include "quiche/quic/core/quic_data_writer.h"
 #include "quiche/quic/core/quic_interval.h"
-#include "quiche/quic/core/quic_utils.h"
+#include "quiche/quic/core/quic_interval_set.h"
+#include "quiche/quic/core/quic_types.h"
 #include "quiche/quic/platform/api/quic_bug_tracker.h"
-#include "quiche/quic/platform/api/quic_flag_utils.h"
 #include "quiche/quic/platform/api/quic_flags.h"
 #include "quiche/quic/platform/api/quic_logging.h"
+#include "quiche/common/platform/api/quiche_logging.h"
 #include "quiche/common/platform/api/quiche_mem_slice.h"
+#include "quiche/common/quiche_buffer_allocator.h"
 
 namespace quic {
 
@@ -50,11 +55,7 @@
 
 QuicStreamSendBuffer::QuicStreamSendBuffer(
     quiche::QuicheBufferAllocator* allocator)
-    : stream_offset_(0),
-      allocator_(allocator),
-      stream_bytes_written_(0),
-      stream_bytes_outstanding_(0),
-      write_index_(-1) {}
+    : allocator_(allocator) {}
 
 QuicStreamSendBuffer::~QuicStreamSendBuffer() {}
 
diff --git a/quiche/quic/core/quic_stream_send_buffer.h b/quiche/quic/core/quic_stream_send_buffer.h
index d87272a..849496b 100644
--- a/quiche/quic/core/quic_stream_send_buffer.h
+++ b/quiche/quic/core/quic_stream_send_buffer.h
@@ -5,13 +5,18 @@
 #ifndef QUICHE_QUIC_CORE_QUIC_STREAM_SEND_BUFFER_H_
 #define QUICHE_QUIC_CORE_QUIC_STREAM_SEND_BUFFER_H_
 
+#include <cstddef>
+#include <cstdint>
+
+#include "absl/strings/string_view.h"
 #include "absl/types/span.h"
-#include "quiche/quic/core/frames/quic_stream_frame.h"
+#include "quiche/quic/core/quic_interval.h"
 #include "quiche/quic/core/quic_interval_deque.h"
 #include "quiche/quic/core/quic_interval_set.h"
 #include "quiche/quic/core/quic_types.h"
+#include "quiche/common/platform/api/quiche_export.h"
 #include "quiche/common/platform/api/quiche_mem_slice.h"
-#include "quiche/common/quiche_circular_deque.h"
+#include "quiche/common/quiche_buffer_allocator.h"
 
 namespace quic {
 
@@ -148,25 +153,21 @@
   QuicIntervalDeque<BufferedSlice> interval_deque_;
 
   // Offset of next inserted byte.
-  QuicStreamOffset stream_offset_;
+  QuicStreamOffset stream_offset_ = 0;
 
   quiche::QuicheBufferAllocator* allocator_;
 
   // Bytes that have been consumed by the stream.
-  uint64_t stream_bytes_written_;
+  uint64_t stream_bytes_written_ = 0;
 
   // Bytes that have been consumed and are waiting to be acked.
-  uint64_t stream_bytes_outstanding_;
+  uint64_t stream_bytes_outstanding_ = 0;
 
   // Offsets of data that has been acked.
   QuicIntervalSet<QuicStreamOffset> bytes_acked_;
 
   // Data considered as lost and needs to be retransmitted.
   QuicIntervalSet<QuicStreamOffset> pending_retransmissions_;
-
-  // Index of slice which contains data waiting to be written for the first
-  // time. -1 if send buffer is empty or all data has been written.
-  int32_t write_index_;
 };
 
 }  // namespace quic
diff --git a/quiche/quic/core/quic_stream_send_buffer_test.cc b/quiche/quic/core/quic_stream_send_buffer_test.cc
index a9f8d3a..d74a757 100644
--- a/quiche/quic/core/quic_stream_send_buffer_test.cc
+++ b/quiche/quic/core/quic_stream_send_buffer_test.cc
@@ -10,7 +10,6 @@
 
 #include "absl/strings/string_view.h"
 #include "quiche/quic/core/quic_data_writer.h"
-#include "quiche/quic/core/quic_utils.h"
 #include "quiche/quic/platform/api/quic_expect_bug.h"
 #include "quiche/quic/platform/api/quic_flags.h"
 #include "quiche/quic/platform/api/quic_test.h"