Convert the PluginService interface to be an async wrapper around PluginList.

chrome/browser/printing/print_preview_tab_controller.cc

Index: chrome/browser/printing/print_preview_tab_controller.cc
diff --git a/chrome/browser/printing/print_preview_tab_controller.cc b/chrome/browser/printing/print_preview_tab_controller.cc
index 10cb9c6be6e773871b4d4635ccc314afdcf4737a..e04c9ebb2553980a089a5baff7f1ec51d0c8b0f9 100644
--- a/chrome/browser/printing/print_preview_tab_controller.cc
+++ b/chrome/browser/printing/print_preview_tab_controller.cc
@@ -22,6 +22,7 @@
 #include "chrome/common/chrome_content_client.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/url_constants.h"
+#include "content/browser/plugin_service.h"
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/tab_contents/navigation_details.h"
 #include "content/browser/tab_contents/tab_contents.h"
@@ -29,11 +30,8 @@
 #include "content/common/notification_details.h"
 #include "content/common/notification_source.h"
 #include "webkit/plugins/npapi/plugin_group.h"
-#include "webkit/plugins/npapi/plugin_list.h"
-#include "webkit/plugins/webplugininfo.h"
 
 using webkit::npapi::PluginGroup;
-using webkit::npapi::PluginList;
 using webkit::WebPluginInfo;
 
 namespace {
@@ -44,7 +42,7 @@ void EnableInternalPDFPluginForTab(TabContentsWrapper* preview_tab) {
       ASCIIToUTF16(chrome::ChromeContentClient::kPDFPluginName));
   PluginGroup* internal_pdf_group = NULL;
   std::vector<PluginGroup> plugin_groups;
-  PluginList::Singleton()->GetPluginGroups(false, &plugin_groups);
+  PluginService::GetInstance()->GetCachedPluginGroups(&plugin_groups);
   for (size_t i = 0; i < plugin_groups.size(); ++i) {
     if (plugin_groups[i].GetGroupName() == internal_pdf_group_name) {
       internal_pdf_group = &plugin_groups[i];