[clang-format][NFC] Use isComment() in setCommentLineLevels()

[owenpan]

Summary

Also replace an unnecessary check with assert() in the unwrapped line parser.

[curdeius]

Thanks for the clean up!

clang/lib/Format/TokenAnnotator.cpp

 
 } // end anonymous namespace
 
 void TokenAnnotator::setCommentLineLevels(
     SmallVectorImpl<AnnotatedLine *> &Lines) {
   const AnnotatedLine *NextNonCommentLine = nullptr;
   for (AnnotatedLine *Line : llvm::reverse(Lines)) {
     assert(Line->First);
-    bool CommentLine = true;
-    for (const FormatToken *Tok = Line->First; Tok; Tok = Tok->Next) {
-      if (!Tok->is(tok::comment)) {
-        CommentLine = false;
-        break;
-      }
-    }
 
     // If the comment is currently aligned with the line immediately following
     // it, that's probably intentional and we should keep it.
-    if (NextNonCommentLine && CommentLine &&
+    if (NextNonCommentLine && Line->isComment() &&
         NextNonCommentLine->First->NewlinesBefore <= 1 &&
         NextNonCommentLine->First->OriginalColumn ==
             Line->First->OriginalColumn) {
       // Align comments for preprocessor lines with the # in column 0 if
       // preprocessor lines are not indented. Otherwise, align with the next
       // line.
       Line->Level =
           (Style.IndentPPDirectives != FormatStyle::PPDIS_BeforeHash &&

clang/lib/Format/UnwrappedLineParser.cpp

if (FormatTok->is(tok::kw_else)) {
     handleAttributes();
     if (FormatTok->is(tok::l_brace)) {
       ElseLeftBrace = FormatTok;
       CompoundStatementIndenter Indenter(this, Style, Line->Level);
       if (parseBlock() == IfStmtKind::IfOnly)
         Kind = IfStmtKind::IfElseIf;
       addUnwrappedLine();
     } else if (FormatTok->is(tok::kw_if)) {
-      FormatToken *Previous = Tokens->getPreviousToken();
-      const bool IsPrecededByComment = Previous && Previous->is(tok::comment);
+      const FormatToken *Previous = Tokens->getPreviousToken();
+      assert(Previous);
+      const bool IsPrecededByComment = Previous->is(tok::comment);
       if (IsPrecededByComment) {
         addUnwrappedLine();
         ++Line->Level;
       }
       bool TooDeep = true;
       if (Style.RemoveBracesLLVM) {
         Kind = IfStmtKind::IfElseIf;
         TooDeep = NestedTooDeep.pop_back_val();