[AST][NFC] Doc comments for ASTNameGenerator

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@371112 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/Mangle.h

@@ -250,8 +250,16 @@ class ASTNameGenerator {
 public:
   explicit ASTNameGenerator(ASTContext &Ctx);
   ~ASTNameGenerator();
+
+  /// Writes name for \p D to \p OS.
+  /// \returns true on failure, false on success.
   bool writeName(const Decl *D, raw_ostream &OS);
+
+  /// \returns name for \p D
   std::string getName(const Decl *D);
+
+  /// \returns all applicable mangled names.
+  /// For example C++ constructors/destructors can have multiple.
   std::vector<std::string> getAllManglings(const Decl *D);
 
 private: