A decimal integer literal with a leading 0 is now an error in strict mode.

src/parsing/parser-base.h

Index: src/parsing/parser-base.h
diff --git a/src/parsing/parser-base.h b/src/parsing/parser-base.h
index ac75fee5c7e9590161d5b93185b69c7cceadbbd0..9f8c735f265c591555f8f95669de850ecb1cfde1 100644
--- a/src/parsing/parser-base.h
+++ b/src/parsing/parser-base.h
@@ -883,19 +883,12 @@ class ParserBase {
       DCHECK_NE(message, MessageTemplate::kNone);
       impl()->ReportMessageAt(octal, message);
       scanner()->clear_octal_position();
+      if (message == MessageTemplate::kStrictDecimalWithLeadingZero) {
+        impl()->CountUsage(v8::Isolate::kDecimalWithLeadingZeroInStrictMode);
+      }
       *ok = false;
     }
   }
-  // for now, this check just collects statistics.
-  void CheckDecimalLiteralWithLeadingZero(int beg_pos, int end_pos) {
-    Scanner::Location token_location =
-        scanner()->decimal_with_leading_zero_position();
-    if (token_location.IsValid() && beg_pos <= token_location.beg_pos &&
-        token_location.end_pos <= end_pos) {
-      scanner()->clear_decimal_with_leading_zero_position();
-      impl()->CountUsage(v8::Isolate::kDecimalWithLeadingZeroInStrictMode);
-    }
-  }
 
   inline void CheckStrictOctalLiteral(int beg_pos, int end_pos, bool* ok) {
     CheckOctalLiteral(beg_pos, end_pos, false, ok);