llvm-pdbdump: If we don't change the color, don't reset the color.

[amccarth]

Summary

The -output-color option was successful at suppressing color changes, but was still allowing color resets.

[inglorion]

lgtm

llvm/trunk/tools/llvm-pdbdump/LinePrinter.h

public:
   WithColor(LinePrinter &P, PDB_ColorItem C);
   ~WithColor();
 
   raw_ostream &get() { return OS; }
 
 private:
   void applyColor(PDB_ColorItem C);
   raw_ostream &OS;
+  bool UseColor;
 };
 }
 }
 
 #endif

llvm/trunk/tools/llvm-pdbdump/LinePrinter.cpp

bool LinePrinter::IsSymbolExcluded(llvm::StringRef SymbolName) {
   return IsItemExcluded(SymbolName, IncludeSymbolFilters, ExcludeSymbolFilters);
 }
 
 bool LinePrinter::IsCompilandExcluded(llvm::StringRef CompilandName) {
   return IsItemExcluded(CompilandName, IncludeCompilandFilters,
                         ExcludeCompilandFilters);
 }
 
-WithColor::WithColor(LinePrinter &P, PDB_ColorItem C) : OS(P.OS) {
-  if (P.hasColor())
+WithColor::WithColor(LinePrinter &P, PDB_ColorItem C)
+    : OS(P.OS), UseColor(P.hasColor()) {
+  if (UseColor)
     applyColor(C);
 }
 
-WithColor::~WithColor() { OS.resetColor(); }
+WithColor::~WithColor() {
+  if (UseColor)
+    OS.resetColor();
+}
 
 void WithColor::applyColor(PDB_ColorItem C) {
   switch (C) {
   case PDB_ColorItem::None:
     OS.resetColor();
     return;
   case PDB_ColorItem::Address:
     OS.changeColor(raw_ostream::YELLOW, /*bold=*/true);