Move the Widget hierarchy to the Oilpan heap.

Source/web/PopupMenuChromium.cpp

Index: Source/web/PopupMenuChromium.cpp
diff --git a/Source/web/PopupMenuChromium.cpp b/Source/web/PopupMenuChromium.cpp
index 053e716d3572d27b36f9dfddafd539f269f46039..b0257e67b9e08373a103134af794f606080ed03c 100644
--- a/Source/web/PopupMenuChromium.cpp
+++ b/Source/web/PopupMenuChromium.cpp
@@ -47,12 +47,26 @@ PopupMenuChromium::PopupMenuChromium(LocalFrame& frame, PopupMenuClient* client)
 
 PopupMenuChromium::~PopupMenuChromium()
 {
+#if !ENABLE(OILPAN)

[haraken, 2014/09/29 14:16:37]

Can we add an assert to oilpan builds to verify that dispose() has been already
called?

[sof, 2014/10/02 14:03:54]

Done.

+    dispose();
+#endif
+}
+
+void PopupMenuChromium::dispose()
+{
     // When the PopupMenuChromium is destroyed, the client could already have been deleted.
     if (m_popup)
         m_popup->disconnectClient();
     hide();
 }
 
+void PopupMenuChromium::trace(Visitor* visitor)
+{
+    visitor->trace(m_frameView);
+    visitor->trace(m_popup);
+    PopupMenu::trace(visitor);
+}
+
 void PopupMenuChromium::show(const FloatQuad& controlPosition, const IntSize& controlSize, int index)
 {
     if (!m_popup) {
@@ -77,6 +91,11 @@ void PopupMenuChromium::updateFromElement()
 void PopupMenuChromium::disconnectClient()
 {
     m_popupClient = 0;
+#if ENABLE(OILPAN)
+    // Cannot be done during finalization, so instead done when the
+    // render object is destroyed and disconnected.
+    dispose();

[haraken, 2014/09/29 14:16:37]

How about making non-oilpan builds call dispose() here as well?

(We don't want to have different behavior between oilpan builds and non-oilpan
builds as much as possible.)

[sof, 2014/10/02 14:03:54]

That's always preferable and I suspect that might work out in this case, but my
preference is to handle that separately to reduce risk. Added a FIXME.

+#endif
 }
 
 } // namespace blink