Revert 111252 - Switch MHTMLGenerationManager to use a Callback.

chrome/browser/extensions/extension_save_page_api.cc

 // Copyright (c) 2011 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/extensions/extension_save_page_api.h"
 
-#include "base/bind.h"
 #include "base/file_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "content/browser/child_process_security_policy.h"
 #include "content/browser/renderer_host/render_view_host.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "content/browser/download/mhtml_generation_manager.h"
 #include "content/public/browser/notification_details.h"
@@ skipping 81 matching lines @@
   // no longer used.
   mhtml_file_ = webkit_blob::DeletableFileReference::GetOrCreate(mhtml_path_,
       BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
 
   TabContents* tab_contents = GetTabContents();
   if (!tab_contents) {
     ReturnFailure(kTabClosedError);
     return;
   }
 
-  MHTMLGenerationManager::GenerateMHTMLCallback callback =
-      base::Bind(&SavePageAsMHTMLFunction::MHTMLGenerated, this);
-
+  registrar_.Add(
+      this, content::NOTIFICATION_MHTML_GENERATED,
+      content::Source<RenderViewHost>(tab_contents->render_view_host()));
+  // TODO(jcivelli): we should listen for navigation in the tab, tab closed,
+  //                 renderer died.
   g_browser_process->mhtml_generation_manager()->GenerateMHTML(
-      tab_contents, mhtml_path_, callback);
+      tab_contents, mhtml_path_);
 }
 
-void SavePageAsMHTMLFunction::MHTMLGenerated(const FilePath& file_path,
-                                             int64 mhtml_file_size) {
-  DCHECK(mhtml_path_ == file_path);
-  if (mhtml_file_size <= 0) {
+void SavePageAsMHTMLFunction::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  DCHECK(type == content::NOTIFICATION_MHTML_GENERATED);
+
+  const MHTMLGenerationManager::NotificationDetails* save_details =
+      content::Details<MHTMLGenerationManager::NotificationDetails>(details).
+          ptr();
+
+  if (mhtml_path_ != save_details->file_path) {
+    // This could happen if there are concurrent MHTML generations going on for
+    // the same tab.
+    LOG(WARNING) << "Received a notification that MHTML was generated but for a"
+        " different file.";
+    return;
+  }
+
+  registrar_.RemoveAll();
+
+  if (save_details->file_size <= 0) {
     ReturnFailure(kMHTMLGenerationFailedError);
     return;
   }
 
-  if (mhtml_file_size > std::numeric_limits<int>::max()) {
+  if (save_details->file_size > std::numeric_limits<int>::max()) {
     ReturnFailure(kFileTooBigError);
     return;
   }
 
-  ReturnSuccess(mhtml_file_size);
+  ReturnSuccess(save_details->file_size);
 }
 
 void SavePageAsMHTMLFunction::ReturnFailure(const std::string& error) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   error_ = error;
 
   SendResponse(false);
 
   Release();  // Balanced in Run()
@@ skipping 27 matching lines @@
 TabContents* SavePageAsMHTMLFunction::GetTabContents() {
   Browser* browser = NULL;
   TabContentsWrapper* tab_contents_wrapper = NULL;
 
   if (!ExtensionTabUtil::GetTabById(tab_id_, profile(), include_incognito(),
       &browser, NULL, &tab_contents_wrapper, NULL)) {
     return NULL;
   }
   return tab_contents_wrapper->tab_contents();
 }