message: Use StringRef::drop_while() to simplify a while loop
diff: @@ -710,12 +710,10 @@ static bool isDialectTypeSimpleEnoughForPrettyForm(StringRef typeName) {
  // Ignore all the characters that are valid in an identifier in the type
  // name.
  - while (isalpha(typeName.front()) || isdigit(typeName.front()) ||
  - typeName.front() == '.') {
  - typeName = typeName.drop_front();
  + typeName =
  + typeName.drop_while([](char c) { return llvm::isAlnum(c) || c == '.'; });
  if (typeName.empty())
  return true;
  - }
  // If we got to an unexpected character, then it must be a <>. Check those
  // recursively.
  