message: Attempt to fix windows unit tests
  In LLVM r296049, IPDBSession::getGlobalScope lost its constness. Adjust
  the unittest to account for that.
diff: @@ -120,7 +120,7 @@ protected:
  return false;
  }
  - uint64_t GetGlobalConstantInteger(const llvm::pdb::IPDBSession &session,
  + uint64_t GetGlobalConstantInteger(llvm::pdb::IPDBSession &session,
  llvm::StringRef var) const {
  auto global = session.getGlobalScope();
  auto results =
  @@ -371,7 +371,7 @@ TEST_F(SymbolFilePDBTests, TestSimpleClassTypes) {
  SymbolVendor *plugin = module->GetSymbolVendor();
  SymbolFilePDB *symfile =
  static_cast<SymbolFilePDB *>(plugin->GetSymbolFile());
  - const llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  + llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  SymbolContext sc;
  llvm::DenseSet<SymbolFile *> searched_files;
  TypeMap results;
  @@ -394,7 +394,7 @@ TEST_F(SymbolFilePDBTests, TestNestedClassTypes) {
  SymbolVendor *plugin = module->GetSymbolVendor();
  SymbolFilePDB *symfile =
  static_cast<SymbolFilePDB *>(plugin->GetSymbolFile());
  - const llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  + llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  SymbolContext sc;
  llvm::DenseSet<SymbolFile *> searched_files;
  TypeMap results;
  @@ -417,7 +417,7 @@ TEST_F(SymbolFilePDBTests, TestClassInNamespace) {
  SymbolVendor *plugin = module->GetSymbolVendor();
  SymbolFilePDB *symfile =
  static_cast<SymbolFilePDB *>(plugin->GetSymbolFile());
  - const llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  + llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  SymbolContext sc;
  llvm::DenseSet<SymbolFile *> searched_files;
  TypeMap results;
  @@ -440,7 +440,7 @@ TEST_F(SymbolFilePDBTests, TestEnumTypes) {
  SymbolVendor *plugin = module->GetSymbolVendor();
  SymbolFilePDB *symfile =
  static_cast<SymbolFilePDB *>(plugin->GetSymbolFile());
  - const llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  + llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  SymbolContext sc;
  llvm::DenseSet<SymbolFile *> searched_files;
  const char *EnumsToCheck[] = {"Enum", "ShortEnum"};
  @@ -487,7 +487,7 @@ TEST_F(SymbolFilePDBTests, TestTypedefs) {
  SymbolVendor *plugin = module->GetSymbolVendor();
  SymbolFilePDB *symfile =
  static_cast<SymbolFilePDB *>(plugin->GetSymbolFile());
  - const llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  + llvm::pdb::IPDBSession &session = symfile->GetPDBSession();
  SymbolContext sc;
  llvm::DenseSet<SymbolFile *> searched_files;
  TypeMap results;
  