Use PluginPrefs in ChromePluginServiceFilter to check whether a plugin is enabled.

chrome/browser/profiles/profile_io_data.cc

Index: chrome/browser/profiles/profile_io_data.cc
diff --git a/chrome/browser/profiles/profile_io_data.cc b/chrome/browser/profiles/profile_io_data.cc
index 31a9e1aba971abb34018b75e15a06a566e786500..3a0adbdbd30a127286da882b2a907159a87d2387 100644
--- a/chrome/browser/profiles/profile_io_data.cc
+++ b/chrome/browser/profiles/profile_io_data.cc
@@ -15,6 +15,7 @@
 #include "base/string_number_conversions.h"
 #include "base/task.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_plugin_service_filter.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
 #include "chrome/browser/extensions/extension_info_map.h"
@@ -191,6 +192,9 @@ void ProfileIOData::InitializeProfileParams(Profile* profile) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   PrefService* pref_service = profile->GetPrefs();
 
+  ChromePluginServiceFilter::GetInstance()->RegisterResourceContext(
+      profile, resource_context_);
+
   scoped_ptr<ProfileParams> params(new ProfileParams);
   params->is_incognito = profile->IsOffTheRecord();
   params->clear_local_state_on_exit =
@@ -508,6 +512,8 @@ void ProfileIOData::ShutdownOnUIThread() {
   enable_referrers_.Destroy();
   clear_local_state_on_exit_.Destroy();
   safe_browsing_enabled_.Destroy();
+  ChromePluginServiceFilter::GetInstance()->UnregisterResourceContext(
+      resource_context_);
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::Bind(