Make the UI an observer of downloads.

chrome/browser/ui/browser.cc

 // Copyright 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/browser.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #endif  // defined(OS_WIN)
@@ skipping 1219 matching lines @@
   // Instant overlay state.
   // ModeChanged() updates bookmark bar state for all mode transitions except
   // when new mode is |SEARCH_SUGGESTIONS|, because that needs to be done when
   // the suggestions are ready.
   if (mode.is_search_suggestions() &&
       bookmark_bar_state_ == BookmarkBar::SHOW) {
     UpdateBookmarkBarState(BOOKMARK_BAR_STATE_CHANGE_TAB_STATE);
   }
 }
 
+void Browser::ShowDownload(content::DownloadItem* download) {
+  if (!window())
+    return;
+
+  // If the download occurs in a new tab, and it's not a save page
+  // download (started before initial navigation completed) close it.
+  WebContents* source = download->GetWebContents();
+  if (source && source->GetController().IsInitialNavigation() &&
+      tab_strip_model_->count() > 1 && !download->IsSavePackageDownload()) {
+    CloseContents(source);
+  }
+
+  // Some (app downloads) are not supposed to appear on the shelf.
+  if (!DownloadItemModel(download).ShouldShowInShelf())
+    return;
+
+  // GetDownloadShelf creates the download shelf if it was not yet created.
+  DownloadShelf* shelf = window()->GetDownloadShelf();
+  shelf->AddDownload(download);
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Browser, content::WebContentsDelegate implementation:
 
 WebContents* Browser::OpenURLFromTab(WebContents* source,
                                      const OpenURLParams& params) {
   chrome::NavigateParams nav_params(this, params.url, params.transition);
   nav_params.source_contents = source;
   nav_params.referrer = params.referrer;
   nav_params.extra_headers = params.extra_headers;
   nav_params.disposition = params.disposition;
@@ skipping 145 matching lines @@
 }
 
 void Browser::RenderWidgetShowing() {
   window_->DisableInactiveFrame();
 }
 
 int Browser::GetExtraRenderViewHeight() const {
   return window_->GetExtraRenderViewHeight();
 }
 
-void Browser::OnStartDownload(WebContents* source,
-                              content::DownloadItem* download) {
-  if (!DownloadItemModel(download).ShouldShowInShelf())
-    return;
-
-  WebContents* constrained = GetConstrainingWebContents(source);
-  if (constrained != source) {
-    // Download in a constrained popup is shown in the tab that opened it.
-    constrained->GetDelegate()->OnStartDownload(constrained, download);
-    return;
-  }
-
-  if (!window())
-    return;
-
-  // GetDownloadShelf creates the download shelf if it was not yet created.
-  DownloadShelf* shelf = window()->GetDownloadShelf();
-  shelf->AddDownload(download);
-
-  // If the download occurs in a new tab, and it's not a save page
-  // download (started before initial navigation completed), close it.
-  if (source->GetController().IsInitialNavigation() &&
-      tab_strip_model_->count() > 1 && !download->IsSavePackageDownload())
-    CloseContents(source);
-}
-
 void Browser::ViewSourceForTab(WebContents* source, const GURL& page_url) {
   DCHECK(source);
   chrome::ViewSource(this, source);
 }
 
 void Browser::ViewSourceForFrame(WebContents* source,
                                  const GURL& frame_url,
                                  const std::string& frame_content_state) {
   DCHECK(source);
   chrome::ViewSource(this, source, frame_url, frame_content_state);
@@ skipping 818 matching lines @@
   if (contents && !allow_js_access) {
     contents->web_contents()->GetController().LoadURL(
         target_url,
         content::Referrer(),
         content::PAGE_TRANSITION_LINK,
         std::string());  // No extra headers.
   }
 
   return contents != NULL;
 }