Don't peek when parsing mixin applications.

pkg/front_end/lib/src/incremental/unlinked_unit.dart

Index: pkg/front_end/lib/src/incremental/unlinked_unit.dart
diff --git a/pkg/front_end/lib/src/incremental/unlinked_unit.dart b/pkg/front_end/lib/src/incremental/unlinked_unit.dart
index f657b5d2d1e6165cafae77a8cdb02a35fe0580d2..9287a14c5d07f715f68074a3f9a3ebbf2210c0f6 100644
--- a/pkg/front_end/lib/src/incremental/unlinked_unit.dart
+++ b/pkg/front_end/lib/src/incremental/unlinked_unit.dart
@@ -119,8 +119,8 @@ class _BodySkippingParser extends Parser {
     return super.parseFunctionBody(token, isExpression, allowAbstract);
   }
 
-  Token parseMixinApplication(Token token) {
+  Token parseMixinApplicationRest(Token token) {
     hasMixin = true;
-    return super.parseMixinApplication(token);
+    return super.parseMixinApplicationRest(token);
   }
 }