Limit depth of parsing of dictionaries returned by JS evaluation.

ios/web/web_state/ui/web_view_js_utils.h

Index: ios/web/web_state/ui/web_view_js_utils.h
diff --git a/ios/web/web_state/ui/web_view_js_utils.h b/ios/web/web_state/ui/web_view_js_utils.h
index 22674d18102142596e0c99bfdf0faff36a6795bb..464c4f4e02ffb1f76ba89a86ee579b9216f0d018 100644
--- a/ios/web/web_state/ui/web_view_js_utils.h
+++ b/ios/web/web_state/ui/web_view_js_utils.h
@@ -21,6 +21,9 @@ namespace web {
 // The domain for JS evaluation NSErrors in web.
 extern NSString* const kJSEvaluationErrorDomain;
 
+// The maximum recursion depth when parsing JS results.
+extern int const kMaximumParsingRecursionDepth;
+
 // The type of errors that can occur while evaluating JS.
 enum JSEvaluationErrorCode {
   // No web view present to evaluate JS.