[Win] Add reporting of total number of modules loaded in browser process.

chrome/browser/ui/webui/conflicts_ui.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 "chrome/browser/ui/webui/conflicts_ui.h"
 
 #if defined(OS_WIN)
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "build/build_config.h"
-#include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/win/enumerate_modules_model.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-#include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "content/public/browser/web_ui_message_handler.h"
 #include "grit/browser_resources.h"
 #include "grit/components_strings.h"
 #include "grit/theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/layout.h"
@@ skipping 32 matching lines @@
   source->SetDefaultResource(IDR_ABOUT_CONFLICTS_HTML);
   return source;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 //
 // ConflictsDOMHandler
 //
 ////////////////////////////////////////////////////////////////////////////////
 
-// The handler for JavaScript messages for the about:flags page.
+// The handler for JavaScript messages for the about:conflicts page.
 class ConflictsDOMHandler : public WebUIMessageHandler,
-                            public content::NotificationObserver {
+                            public EnumerateModulesModel::Observer {
  public:
   ConflictsDOMHandler() {}
   ~ConflictsDOMHandler() override {}
 
   // WebUIMessageHandler implementation.
   void RegisterMessages() override;
 
   // Callback for the "requestModuleList" message.
   void HandleRequestModuleList(const base::ListValue* args);
 
  private:
   void SendModuleList();
 
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
-  content::NotificationRegistrar registrar_;
+  // EnumerateModulesModel::Observer implementation.
+  void OnScanCompleted() override;
 
   DISALLOW_COPY_AND_ASSIGN(ConflictsDOMHandler);
 };
 
 void ConflictsDOMHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback("requestModuleList",
       base::Bind(&ConflictsDOMHandler::HandleRequestModuleList,
                  base::Unretained(this)));
 }
 
 void ConflictsDOMHandler::HandleRequestModuleList(const base::ListValue* args) {
-  // This request is handled asynchronously. See Observe for when we reply back.
-  registrar_.Add(this, chrome::NOTIFICATION_MODULE_LIST_ENUMERATED,
-                 content::NotificationService::AllSources());
-  EnumerateModulesModel::GetInstance()->ScanNow();
+  // The request is handled asynchronously, and will callback via
+  // OnScanCompleted on completion.
+  auto model = EnumerateModulesModel::GetInstance();

[Lei Zhang, 2016/08/04 14:33:32]

auto*

[chrisha, 2016/08/12 19:04:40]

Done.

+  model->AddObserver(this);

[Lei Zhang, 2016/08/04 14:33:32]

Can this end up adding the same observer twice? This is a JS handler right? Can
JS send 2 requestModuleList messages before OnScanCompleted() ?

[Peter Kasting, 2016/08/05 00:10:08]

If this is a real concern, using a ScopedObserver would allow this to be checked
simply using the IsObserving() method.  OTOH, that's a less-helpful pattern
otherwise in this class, since the RemoveObserver call does not happen at
destruction.  (Although, do you need to worry about being destroyed without
OnScanCompleted() being reached?  Because if so then you do need such a call.)

[chrisha, 2016/08/12 19:04:40]

The ScopedObserver is cleaner IMO, and also allows me to handle this possible
case of 'abuse' from the JS. Switched to using that.

[chrisha, 2016/08/12 19:04:40]

Shouldn't be possible from how the JS code is written, but using a
ScopedObserver to safely handle this case is easy enough.

+  model->ScanNow();
 }
 
 void ConflictsDOMHandler::SendModuleList() {
   EnumerateModulesModel* loaded_modules = EnumerateModulesModel::GetInstance();
   base::ListValue* list = loaded_modules->GetModuleList();
   base::DictionaryValue results;
   results.Set("moduleList", list);
 
   // Add the section title and the total count for bad modules found.
   int confirmed_bad = loaded_modules->confirmed_bad_modules_detected();
   int suspected_bad = loaded_modules->suspected_bad_modules_detected();
   base::string16 table_title;
   if (!confirmed_bad && !suspected_bad) {
     table_title += l10n_util::GetStringFUTF16(
         IDS_CONFLICTS_CHECK_PAGE_TABLE_TITLE_SUFFIX_ONE,
             base::IntToString16(list->GetSize()));
   } else {
     table_title += l10n_util::GetStringFUTF16(
         IDS_CONFLICTS_CHECK_PAGE_TABLE_TITLE_SUFFIX_TWO,
             base::IntToString16(list->GetSize()),
             base::IntToString16(confirmed_bad),
             base::IntToString16(suspected_bad));
   }
   results.SetString("modulesTableTitle", table_title);
 
   web_ui()->CallJavascriptFunctionUnsafe("returnModuleList", results);
 }
 
-void ConflictsDOMHandler::Observe(int type,
-                                  const content::NotificationSource& source,
-                                  const content::NotificationDetails& details) {
-  DCHECK_EQ(chrome::NOTIFICATION_MODULE_LIST_ENUMERATED, type);
-
+void ConflictsDOMHandler::OnScanCompleted() {
   SendModuleList();
-  registrar_.RemoveAll();
+  EnumerateModulesModel::GetInstance()->RemoveObserver(this);
 }
 
 }  // namespace
 
 ///////////////////////////////////////////////////////////////////////////////
 //
 // ConflictsUI
 //
 ///////////////////////////////////////////////////////////////////////////////
 
 ConflictsUI::ConflictsUI(content::WebUI* web_ui) : WebUIController(web_ui) {
   content::RecordAction(UserMetricsAction("ViewAboutConflicts"));
   web_ui->AddMessageHandler(new ConflictsDOMHandler());
 
   // Set up the about:conflicts source.
   Profile* profile = Profile::FromWebUI(web_ui);
   content::WebUIDataSource::Add(profile, CreateConflictsUIHTMLSource());
 }
 
 // static
 base::RefCountedMemory* ConflictsUI::GetFaviconResourceBytes(
       ui::ScaleFactor scale_factor) {
   return static_cast<base::RefCountedMemory*>(
       ResourceBundle::GetSharedInstance().LoadDataResourceBytesForScale(
           IDR_CONFLICT_FAVICON, scale_factor));
 }
 
 #endif