Oilpan: move WorkerGlobalScope to oilpan's heap.

Source/core/workers/WorkerGlobalScope.cpp

Index: Source/core/workers/WorkerGlobalScope.cpp
diff --git a/Source/core/workers/WorkerGlobalScope.cpp b/Source/core/workers/WorkerGlobalScope.cpp
index a517c8704513d3fd0cbcb0632728b7eb664c560b..b9247270e47ba4bd931cc49470eaa94b216485a7 100644
--- a/Source/core/workers/WorkerGlobalScope.cpp
+++ b/Source/core/workers/WorkerGlobalScope.cpp
@@ -92,12 +92,7 @@ WorkerGlobalScope::WorkerGlobalScope(const KURL& url, const String& userAgent, W
 
 WorkerGlobalScope::~WorkerGlobalScope()
 {
-    ASSERT(thread()->isCurrentThread());
-
-    // Notify proxy that we are going away. This can free the WorkerThread object, so do not access it after this.
-    thread()->workerReportingProxy().workerGlobalScopeDestroyed();
-
-    setClient(0);
+    ASSERT(!m_thread);
 }
 
 void WorkerGlobalScope::applyContentSecurityPolicyFromString(const String& policy, ContentSecurityPolicy::HeaderType contentSecurityPolicyType)
@@ -189,6 +184,19 @@ void WorkerGlobalScope::clearInspector()
     m_workerInspectorController.clear();
 }
 
+void WorkerGlobalScope::detach()

[Mads Ager (chromium), 2014/02/26 10:22:40]

I really like this restructuring, thanks! :)

+{
+    ASSERT(thread()->isCurrentThread());
+
+    // Notify proxy that we are going away. This can free the WorkerThread object, so do not access it after this.
+    thread()->workerReportingProxy().workerGlobalScopeDestroyed();
+
+    clearScript();
+    clearInspector();
+    setClient(0);
+    clearThread();
+}
+
 void WorkerGlobalScope::importScripts(const Vector<String>& urls, ExceptionState& exceptionState)
 {
     ASSERT(contentSecurityPolicy());
@@ -280,4 +288,11 @@ WorkerEventQueue* WorkerGlobalScope::eventQueue() const
     return m_eventQueue.get();
 }
 
+void WorkerGlobalScope::trace(Visitor* visitor)

[Mads Ager (chromium), 2014/02/26 10:22:40]

Don't we need an explicit call to WorkerSupplementable::trace(visitor) in
anything that is WorkerSupplementable (WillBeHeapSupplementable) to get the
tracing of the supplements.

I think we carefully need to step through this code to see that we get the right
visiting behavior here.

[sof, 2014/02/26 12:25:13]

Yes, thank you. This is a major oversight when adding these GCed
supplementables; it happened to work as the supplements weren't GCed, so they
were kept alive..forever, leaking.

So, all Supplementable objects that are heap allocated must in their trace()
delegate to the Supplementable's trace().

+{
+    visitor->trace(m_console);
+    visitor->trace(m_location);
+    visitor->trace(m_navigator);
+}
+
 } // namespace WebCore