[modularize] Use std::tie to implement operator< (NFC) (llvm#139410)

Author: kazutakahirata

clang-tools-extra/modularize/Modularize.cpp

@@ -406,11 +406,8 @@ struct Location {
   }
 
   friend bool operator<(const Location &X, const Location &Y) {
-    if (X.File != Y.File)
-      return X.File < Y.File;
-    if (X.Line != Y.Line)
-      return X.Line < Y.Line;
-    return X.Column < Y.Column;
+    return std::tie(X.File, X.Line, X.Column) <
+           std::tie(Y.File, Y.Line, Y.Column);
   }
   friend bool operator>(const Location &X, const Location &Y) { return Y < X; }
   friend bool operator<=(const Location &X, const Location &Y) {

clang-tools-extra/modularize/PreprocessorTracker.cpp

@@ -494,19 +494,8 @@ class PPItemKey {
     return Column == Other.Column;
   }
   bool operator<(const PPItemKey &Other) const {
-    if (Name < Other.Name)
-      return true;
-    else if (Name > Other.Name)
-      return false;
-    if (File < Other.File)
-      return true;
-    else if (File > Other.File)
-      return false;
-    if (Line < Other.Line)
-      return true;
-    else if (Line > Other.Line)
-      return false;
-    return Column < Other.Column;
+    return std::tie(Name, File, Line, Column) <
+           std::tie(Other.Name, Other.File, Other.Line, Other.Column);
   }
   StringHandle Name;
   HeaderHandle File;