[ARC] Converts part of ios/web/public to ARC.

ios/web/BUILD.gn

Index: ios/web/BUILD.gn
diff --git a/ios/web/BUILD.gn b/ios/web/BUILD.gn
index 77b52c39f797e7ef6aacadc9fd1e32b906962628..80bff5f48fdd3dced8497e3fef5ded64e26a1625 100644
--- a/ios/web/BUILD.gn
+++ b/ios/web/BUILD.gn
@@ -104,6 +104,21 @@ source_set("web_arc") {
     "public/interstitials/web_interstitial.h",
     "public/interstitials/web_interstitial_delegate.h",
     "public/java_script_dialog_callback.h",
+    "public/java_script_dialog_presenter.h",
+    "public/java_script_dialog_type.h",
+    "public/load_committed_details.h",
+    "public/navigation_item.h",
+    "public/navigation_manager.h",
+    "public/origin_util.h",
+    "public/origin_util.mm",
+    "public/payments/payment_request.h",
+    "public/referrer.h",
+    "public/referrer_util.cc",
+    "public/referrer_util.h",
+    "public/security_style.h",
+    "public/ssl_status.cc",
+    "public/ssl_status.h",
+    "public/string_util.h",
     "string_util.cc",
     "url_scheme_util.mm",
     "url_util.cc",
@@ -169,21 +184,6 @@ source_set("web") {
   ]
 
   sources = [
-    "public/java_script_dialog_presenter.h",
-    "public/java_script_dialog_type.h",
-    "public/load_committed_details.h",
-    "public/navigation_item.h",
-    "public/navigation_manager.h",
-    "public/origin_util.h",
-    "public/origin_util.mm",
-    "public/payments/payment_request.h",
-    "public/referrer.h",
-    "public/referrer_util.cc",
-    "public/referrer_util.h",
-    "public/security_style.h",
-    "public/ssl_status.cc",
-    "public/ssl_status.h",
-    "public/string_util.h",
     "public/url_data_source_ios.h",
     "public/url_scheme_util.h",
     "public/url_schemes.h",