[clang-format][NFC] Put all state change into the for statement

[curdeius]

LGTM.

clang/lib/Format/UnwrappedLineFormatter.cpp

unsigned UnwrappedLineFormatter::format(
   const AnnotatedLine *NextLine = nullptr;
 
   // The minimum level of consecutive lines that have been formatted.
   unsigned RangeMinLevel = UINT_MAX;
 
   bool FirstLine = true;
   for (const AnnotatedLine *Line =
            Joiner.getNextMergedLine(DryRun, IndentTracker);
-       Line; Line = NextLine, FirstLine = false) {
+       Line; PrevPrevLine = PreviousLine, PreviousLine = Line, Line = NextLine,
+                           FirstLine = false) {
     const AnnotatedLine &TheLine = *Line;
     unsigned Indent = IndentTracker.getIndent();
 
     // We continue formatting unchanged lines to adjust their indent, e.g. if a
     // scope was added. However, we need to carefully stop doing this when we
     // exit the scope of affected lines to prevent indenting a the entire
     // remaining file if it currently missing a closing brace.
     bool PreviousRBrace =
if (ShouldFormat && TheLine.Type != LT_Invalid) {
         for (FormatToken *Tok = TheLine.First->Next; Tok; Tok = Tok->Next)
           Whitespaces->addUntouchableToken(*Tok, TheLine.InPPDirective);
       }
       NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
       RangeMinLevel = UINT_MAX;
     }
     if (!DryRun)
       markFinalized(TheLine.First);
-    PrevPrevLine = PreviousLine;
-    PreviousLine = &TheLine;
   }
   PenaltyCache[CacheKey] = Penalty;
   return Penalty;
 }
 
 void UnwrappedLineFormatter::formatFirstToken(
     const AnnotatedLine &Line, const AnnotatedLine *PreviousLine,
     const AnnotatedLine *PrevPrevLine,