Wrangle MixedArrayDimensions to be an error internally, but not ext…

…ernally.

I added the third_party exemption proactively, and had to hardcode _one last annoying exemption_.

PiperOrigin-RevId: 621130845

core/src/main/java/com/google/errorprone/bugpatterns/MixedArrayDimensions.java

@@ -74,9 +74,11 @@ private Description checkArrayDimensions(Tree tree, Tree type, VisitorState stat
         int idx = dim.indexOf("[]", nonWhitespace);
         if (idx > nonWhitespace) {
           String replacement = dim.substring(idx) + dim.substring(0, idx);
-          // SimpleCharStream generates violations in other packages, and is challenging to fix.
+          // javacc generates classes in arbitrary packages with violations that are hard to fix.
           var enclosingClass = enclosingClass(getSymbol(tree));
-          if (enclosingClass != null && enclosingClass.name.contentEquals("SimpleCharStream")) {
+          if (enclosingClass != null
+              && (enclosingClass.name.contentEquals("SimpleCharStream")
+                  || enclosingClass.name.contentEquals("SimpleNode"))) {
             return NO_MATCH;
           }
           return describeMatch(tree, SuggestedFix.replace(start, end, replacement));