Some cleanup for libpdb.

This patch implements a few of the optional suggestions from the
initial patch comitting libpdb.  In particular, it implements a
virtual function out of line for each of the concrete classes.

A few other minor cleanups exist as well, such as using override
instead of virtual, etc.

llvm-svn: 228516
diff --git a/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp b/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp
new file mode 100644
index 0000000..cf7dc80
--- /dev/null
+++ b/llvm/lib/DebugInfo/PDB/PDBSymbolExe.cpp
@@ -0,0 +1,45 @@
+//===- PDBSymbolExe.cpp - ---------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+
+#include "llvm/DebugInfo/PDB/PDBSymbol.h"
+#include "llvm/DebugInfo/PDB/PDBSymbolExe.h"
+#include "llvm/Support/ConvertUTF.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/raw_ostream.h"
+
+#if defined(_WIN32)
+#include <windows.h>
+#endif
+
+using namespace llvm;
+
+namespace {
+std::string GuidToString(PDB_UniqueId *Id) {
+#if defined(_WIN32)
+  GUID *Guid = reinterpret_cast<GUID *>(Id);
+  OLECHAR GuidBuf[40];
+  int Result = StringFromGUID2(*Guid, GuidBuf, 39);
+  const char *InputBytes = reinterpret_cast<const char *>(GuidBuf);
+  std::string ResultString;
+  convertUTF16ToUTF8String(ArrayRef<char>(InputBytes, Result * 2),
+                           ResultString);
+  return ResultString;
+#else
+  return std::string();
+#endif
+}
+}
+
+PDBSymbolExe::PDBSymbolExe(std::unique_ptr<IPDBRawSymbol> Symbol)
+    : PDBSymbol(std::move(Symbol)) {}
+
+void PDBSymbolExe::dump(llvm::raw_ostream &OS) const {
+}