[v8 gc] Introduce a base class for all objects that can have pending activity

third_party/WebKit/Source/core/page/EventSource.cpp

Index: third_party/WebKit/Source/core/page/EventSource.cpp
diff --git a/third_party/WebKit/Source/core/page/EventSource.cpp b/third_party/WebKit/Source/core/page/EventSource.cpp
index 5d424c33f7745cb8c19745cf9967a466b3a8fed0..cbe8d51b3e4b7bdba4832fdad6c64e034af38a1c 100644
--- a/third_party/WebKit/Source/core/page/EventSource.cpp
+++ b/third_party/WebKit/Source/core/page/EventSource.cpp
@@ -61,7 +61,8 @@ namespace blink {
 const unsigned long long EventSource::defaultReconnectDelay = 3000;
 
 inline EventSource::EventSource(ExecutionContext* context, const KURL& url, const EventSourceInit& eventSourceInit)
-    : ActiveDOMObject(context)
+    : ActiveScriptWrappable(this)
+    , ActiveDOMObject(context)
     , m_url(url)
     , m_withCredentials(eventSourceInit.withCredentials())
     , m_state(CONNECTING)