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

content/plugin/plugin_channel.cc

 // 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.
 
 #include "content/plugin/plugin_channel.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/process/process_handle.h"
 #include "base/strings/string_util.h"
@@ skipping 235 matching lines @@
 }
 
 bool PluginChannel::OnControlMessageReceived(const IPC::Message& msg) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PluginChannel, msg)
     IPC_MESSAGE_HANDLER(PluginMsg_CreateInstance, OnCreateInstance)
     IPC_MESSAGE_HANDLER_DELAY_REPLY(PluginMsg_DestroyInstance,
                                     OnDestroyInstance)
     IPC_MESSAGE_HANDLER(PluginMsg_GenerateRouteID, OnGenerateRouteID)
     IPC_MESSAGE_HANDLER(PluginProcessMsg_ClearSiteData, OnClearSiteData)
-    IPC_MESSAGE_HANDLER(PluginHostMsg_DidAbortLoading, OnDidAbortLoading)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   DCHECK(handled);
   return handled;
 }
 
 void PluginChannel::OnCreateInstance(const std::string& mime_type,
                                      int* instance_id) {
   *instance_id = GenerateRouteID();
   scoped_refptr<WebPluginDelegateStub> stub(new WebPluginDelegateStub(
@@ skipping 53 matching lines @@
           site.empty() ? "NULL"
                        : base::StringPrintf("\"%s\"", site_str);
       VLOG(1) << "NPP_ClearSiteData(" << site_name << ", " << flags << ", "
               << max_age << ") returned " << err;
       success = (err == NPERR_NO_ERROR);
     }
   }
   Send(new PluginProcessHostMsg_ClearSiteDataResult(success));
 }
 
-void PluginChannel::OnDidAbortLoading(int render_view_id) {
-  for (size_t i = 0; i < plugin_stubs_.size(); ++i) {
-    if (plugin_stubs_[i]->webplugin()->host_render_view_routing_id() ==
-            render_view_id) {
-      plugin_stubs_[i]->delegate()->instance()->CloseStreams();
-    }
-  }
-}
-
 }  // namespace content