[ObjC ARC] Converts ios/web/public/test:test to ARC.

ios/web/public/test/web_view_interaction_test_util.mm

Index: ios/web/public/test/web_view_interaction_test_util.mm
diff --git a/ios/web/public/test/web_view_interaction_test_util.mm b/ios/web/public/test/web_view_interaction_test_util.mm
index 9e629c5d7f980c8fc58acb553ce15feaacfae0a6..ba7c7304d044441605139f4b378cd9d07300989b 100644
--- a/ios/web/public/test/web_view_interaction_test_util.mm
+++ b/ios/web/public/test/web_view_interaction_test_util.mm
@@ -14,6 +14,10 @@
 #import "ios/web/web_state/ui/crw_web_view_proxy_impl.h"
 #import "ios/web/web_state/web_state_impl.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 using web::NavigationManager;
 
 namespace web {
@@ -30,7 +34,7 @@ std::unique_ptr<base::Value> ExecuteJavaScript(web::WebState* web_state,
   __block std::unique_ptr<base::Value> result;
   __block bool did_finish = false;
   web_state->ExecuteJavaScript(base::UTF8ToUTF16(script),
-                               base::BindBlock(^(const base::Value* value) {
+                               base::BindBlockArc(^(const base::Value* value) {
                                  if (value)
                                    result = value->CreateDeepCopy();
                                  did_finish = true;