Remove PluginLoadObserver and related logic, it was only used for NPAPI.

content/child/npapi/plugin_stream_url.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_CHILD_NPAPI_PLUGIN_STREAM_URL_H_
 #define CONTENT_CHILD_NPAPI_PLUGIN_STREAM_URL_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "content/child/npapi/plugin_stream.h"
 #include "content/child/npapi/webplugin_resource_client.h"
 #include "url/gurl.h"
 
 namespace content {
 class PluginInstance;
 class PluginURLFetcher;
 
 // A NPAPI Stream based on a URL.
 class PluginStreamUrl : public PluginStream,
                         public WebPluginResourceClient {
  public:
   // Create a new stream for sending to the plugin by fetching
-  // a URL. If notifyNeeded is set, then the plugin will be notified
-  // when the stream has been fully sent to the plugin.  Initialize
-  // must be called before the object is used.
+  // a URL. Initialize must be called before the object is used.
   PluginStreamUrl(unsigned long resource_id,
                   const GURL &url,
-                  PluginInstance *instance,
-                  bool notify_needed,
-                  void *notify_data);
+                  PluginInstance *instance);
 
   void SetPluginURLFetcher(PluginURLFetcher* fetcher);
 
   void URLRedirectResponse(bool allow);
 
   void FetchRange(const std::string& range);
 
   // Stop sending the stream to the client.
   // Overrides the base Close so we can cancel our fetching the URL if
   // it is still loading.
@@ skipping 42 matching lines @@
   std::string pending_redirect_url_;
 
   scoped_ptr<PluginURLFetcher> plugin_url_fetcher_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginStreamUrl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_CHILD_NPAPI_PLUGIN_STREAM_URL_H_