[codeview] Prune SimpleTypeSerializer.h headers, NFC

These are left over from when the class was more complicated. Add a
header comment banner to the .cpp file, which was missing.

llvm/include/llvm/DebugInfo/CodeView/SimpleTypeSerializer.h

@@ -10,25 +10,11 @@
 #define LLVM_DEBUGINFO_CODEVIEW_SIMPLETYPESERIALIZER_H
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/DebugInfo/CodeView/CodeView.h"
-#include "llvm/DebugInfo/CodeView/RecordSerialization.h"
-#include "llvm/DebugInfo/CodeView/TypeIndex.h"
-#include "llvm/DebugInfo/CodeView/TypeRecord.h"
-#include "llvm/DebugInfo/CodeView/TypeRecordMapping.h"
-#include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
-#include "llvm/Support/Allocator.h"
-#include "llvm/Support/BinaryByteStream.h"
-#include "llvm/Support/BinaryStreamWriter.h"
-#include "llvm/Support/Error.h"
-#include <cassert>
-#include <cstdint>
-#include <memory>
 #include <vector>
 
 namespace llvm {
 namespace codeview {
+class FieldListRecord;
 
 class SimpleTypeSerializer {
   std::vector<uint8_t> ScratchBuffer;

llvm/lib/DebugInfo/CodeView/SimpleTypeSerializer.cpp

@@ -1,4 +1,15 @@
+//===- SimpleTypeSerializer.cpp -----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include "llvm/DebugInfo/CodeView/SimpleTypeSerializer.h"
+#include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeRecordMapping.h"
+#include "llvm/Support/BinaryStreamWriter.h"
 
 using namespace llvm;
 using namespace llvm::codeview;

llvm/unittests/DebugInfo/CodeView/RandomAccessVisitorTest.cpp

@@ -14,6 +14,7 @@
 #include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
 #include "llvm/Support/Allocator.h"
+#include "llvm/Support/BinaryByteStream.h"
 #include "llvm/Support/BinaryItemStream.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Testing/Support/Error.h"