[clang-tools-extra] [clang-tidy] Update google todo checker with style guide changes. (PR #165565)

[via cfe-commits]

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@@ -17,28 +17,37 @@ class TodoCommentCheck::TodoCommentHandler : public CommentHandler {
 public:
   TodoCommentHandler(TodoCommentCheck &Check, std::optional<std::string> User)
       : Check(Check), User(User ? *User : "unknown"),
-        TodoMatch("^// *TODO *(\\(.*\\))?:?( )?(.*)$") {}
+        TodoMatch("^// *TODO *((\\((.*)\\))?:?( )?|: *(.*) *- *)?(.*)$") {}
 
   bool HandleComment(Preprocessor &PP, SourceRange Range) override {
     StringRef Text =
         Lexer::getSourceText(CharSourceRange::getCharRange(Range),
                              PP.getSourceManager(), PP.getLangOpts());
 
-    SmallVector<StringRef, 4> Matches;
+    SmallVector<StringRef, 7> Matches;
     if (!TodoMatch.match(Text, &Matches))
       return false;
 
-    StringRef Username = Matches[1];
-    StringRef Comment = Matches[3];
+    const bool deprecated_style = !Matches[3].empty();
+    StringRef Username = deprecated_style ? Matches[5] : Matches[3];
+    StringRef Comment = Matches[6];
 
-    if (!Username.empty())
+    if (!Username.empty() && (deprecated_style || !Comment.empty()))
       return false;
 
-    std::string NewText = ("// TODO(" + Twine(User) + "): " + Comment).str();
+    if (Username.empty()) {
+      std::string NewText = ("// TODO: " + Twine(User) + " - " +
----------------
EugeneZelenko wrote:

```suggestion
      const std::string NewText = ("// TODO: " + Twine(User) + " - " +
```

https://github.com/llvm/llvm-project/pull/165565