Switch SupportsUserData uses to use unique_ptr.

ios/web/webui/url_data_manager_ios.cc

Index: ios/web/webui/url_data_manager_ios.cc
diff --git a/ios/web/webui/url_data_manager_ios.cc b/ios/web/webui/url_data_manager_ios.cc
index ab050d6cdb34e8a042726a2509d2d61147dc79c4..8cb9a5413cd983f298fe48e91ae914d3caffb47f 100644
--- a/ios/web/webui/url_data_manager_ios.cc
+++ b/ios/web/webui/url_data_manager_ios.cc
@@ -10,6 +10,7 @@
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
+#include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
@@ -30,8 +31,9 @@ base::LazyInstance<base::Lock>::Leaky g_delete_lock = LAZY_INSTANCE_INITIALIZER;
 
 URLDataManagerIOS* GetFromBrowserState(BrowserState* browser_state) {
   if (!browser_state->GetUserData(kURLDataManagerIOSKeyName)) {
-    browser_state->SetUserData(kURLDataManagerIOSKeyName,
-                               new URLDataManagerIOS(browser_state));
+    browser_state->SetUserData(
+        kURLDataManagerIOSKeyName,
+        base::MakeUnique<URLDataManagerIOS>(browser_state));
   }
   return static_cast<URLDataManagerIOS*>(
       browser_state->GetUserData(kURLDataManagerIOSKeyName));