Move Renderer-side NPObject owner tracking to JavaBridgeChannel.

content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc

Index: content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc
diff --git a/content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc b/content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc
index bac38564e79fe8bb9bef3ea25f0f3a4a34cd44bf..3e9fd4eeaeea181aabfacea8d4385feec7b39b29 100644
--- a/content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc
+++ b/content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.cc
@@ -20,7 +20,10 @@ namespace content {
 
 JavaBridgeDispatcherHostManager::JavaBridgeDispatcherHostManager(
     WebContents* web_contents)
-    : WebContentsObserver(web_contents) {
+    : WebContentsObserver(web_contents),
+      object_owner_id_(new struct _NPP) {
+  // Register a dummy owner Id for JavaBoundObject instances.
+  WebKit::WebBindings::registerObjectOwner(object_owner_id_.get());
 }
 
 JavaBridgeDispatcherHostManager::~JavaBridgeDispatcherHostManager() {
@@ -29,6 +32,8 @@ JavaBridgeDispatcherHostManager::~JavaBridgeDispatcherHostManager() {
     WebKit::WebBindings::releaseObject(iter->second);
   }
   DCHECK_EQ(0U, instances_.size());
+
+  WebKit::WebBindings::unregisterObjectOwner(object_owner_id_.get());
 }
 
 void JavaBridgeDispatcherHostManager::AddNamedObject(const string16& name,