[parsing] Fix -Wshadow warnings

Bug: v8:12244,v8:12245
Change-Id: I4adafe31ffc747f7184c8b868f97e4a549e619ce
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3273530Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77856}

src/parsing/scanner.cc

@@ -211,7 +211,7 @@ Token::Value Scanner::SkipSingleLineComment() {
   // separately by the lexical grammar and becomes part of the
   // stream of input elements for the syntactic grammar (see
   // ECMA-262, section 7.4).
-  AdvanceUntil([](base::uc32 c0_) { return unibrow::IsLineTerminator(c0_); });
+  AdvanceUntil([](base::uc32 c0) { return unibrow::IsLineTerminator(c0); });
 
   return Token::WHITESPACE;
 }