Add incremental updates for multipage distillation.

components/dom_distiller/core/task_tracker.cc

 // Copyright 2013 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 "components/dom_distiller/core/task_tracker.h"
 
 #include "base/message_loop/message_loop.h"
 #include "components/dom_distiller/core/proto/distilled_article.pb.h"
 #include "components/dom_distiller/core/proto/distilled_page.pb.h"
 
@@ skipping 23 matching lines @@
   }
   if (entry_.pages_size() == 0) {
     return;
   }
 
   GURL url(entry_.pages(0).url());
   DCHECK(url.is_valid());
 
   distiller_ = factory->CreateDistiller();
   distiller_->DistillPage(url,
-                          base::Bind(&TaskTracker::OnDistilledDataReady,
+                          base::Bind(&TaskTracker::OnDistilledArticleReady,
+                                     weak_ptr_factory_.GetWeakPtr()),
+                          base::Bind(&TaskTracker::OnArticleDistillationUpdated,
                                      weak_ptr_factory_.GetWeakPtr()));
 }
 
 void TaskTracker::StartBlobFetcher() {
   // TODO(cjhopman): There needs to be some local storage for the distilled
   // blob. When that happens, this should start some task to fetch the blob for
   // |entry_| and asynchronously notify |this| when it is done.
 }
 
 void TaskTracker::AddSaveCallback(const SaveCallback& callback) {
@@ skipping 77 matching lines @@
     save_callbacks_.clear();
     MaybeCancel();
   }
 }
 
 void TaskTracker::NotifyViewer(ViewRequestDelegate* delegate) {
   DCHECK(distillation_complete_);
   delegate->OnArticleReady(distilled_article_.get());
 }
 
-void TaskTracker::OnDistilledDataReady(
+void TaskTracker::OnDistilledArticleReady(
     scoped_ptr<DistilledArticleProto> distilled_article) {
   distilled_article_ = distilled_article.Pass();
   bool distillation_successful = false;
   if (distilled_article_->pages_size() > 0) {
     distillation_successful = true;
     entry_.set_title(distilled_article_->title());
     // Reset the pages.
     entry_.clear_pages();
     for (int i = 0; i < distilled_article_->pages_size(); ++i) {
       sync_pb::ArticlePage* page = entry_.add_pages();
       page->set_url(distilled_article_->pages(i).url());
     }
   }
 
   distillation_complete_ = true;
 
   for (size_t i = 0; i < viewers_.size(); ++i) {
     NotifyViewer(viewers_[i]);
   }
 
   // Already inside a callback run SaveCallbacks directly.
   DoSaveCallbacks(distillation_successful);
 }
 
+void TaskTracker::OnArticleDistillationUpdated(
+    const ArticleDistillationUpdate& article_update) {
+  for (size_t i = 0; i < viewers_.size(); ++i) {
+    viewers_[i]->OnArticleUpdated(article_update);
+  }
+}
+
 }  // namespace dom_distiller