Work on GN Win64 build.

content/ppapi_plugin/broker_process_dispatcher.cc

Index: content/ppapi_plugin/broker_process_dispatcher.cc
diff --git a/content/ppapi_plugin/broker_process_dispatcher.cc b/content/ppapi_plugin/broker_process_dispatcher.cc
index 35d5b9d48e639ea0cfd5a6e6143115e8ca96c440..97d425043c88248b4ff1a29f549117d5a76cbbd1 100644
--- a/content/ppapi_plugin/broker_process_dispatcher.cc
+++ b/content/ppapi_plugin/broker_process_dispatcher.cc
@@ -309,14 +309,16 @@ bool BrokerProcessDispatcher::SetSitePermission(
 
   if (flash_browser_operations_1_3_) {
     PP_Bool result = flash_browser_operations_1_3_->SetSitePermission(
-        data_str.c_str(), setting_type, sites.size(), site_array.get());
+        data_str.c_str(), setting_type,
+        static_cast<uint32_t>(sites.size()), site_array.get());
 
     return PP_ToBool(result);
   }
 
   if (flash_browser_operations_1_2_) {
     PP_Bool result = flash_browser_operations_1_2_->SetSitePermission(
-        data_str.c_str(), setting_type, sites.size(), site_array.get());
+        data_str.c_str(), setting_type,
+        static_cast<uint32_t>(sites.size()), site_array.get());
 
     return PP_ToBool(result);
   }