Make the UI an observer of downloads.

chrome/browser/ui/browser.cc

Index: chrome/browser/ui/browser.cc
diff --git a/chrome/browser/ui/browser.cc b/chrome/browser/ui/browser.cc
index f1d1d7dcd4ee502a62019b6aeec6220704ccb12e..772672f8a075b8e095e3a4f4d4390bca8b834add 100644
--- a/chrome/browser/ui/browser.cc
+++ b/chrome/browser/ui/browser.cc
@@ -1334,6 +1334,41 @@ void Browser::MaybeUpdateBookmarkBarStateForInstantPreview(
   }
 }
 
+void Browser::ShowDownload(content::DownloadItem* download) {
+  scoped_ptr<DownloadItemModel> download_model(new DownloadItemModel(download));

[Randy Smith (Not in Mondays), 2012/12/25 23:05:54]

Why before bailing if the window isn't there?

[asanka, 2013/01/10 22:12:14]

Done. Note that https://codereview.chromium.org/11673004/ is removing some of
this code.

+  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_count() > 1 && !download->IsSavePackageDownload()) {
+    CloseContents(source);
+  }
+
+  // Some (app downloads) are not supposed to appear on the shelf.
+  if (!download_model->ShouldShowInShelf())
+    return;
+
+  // GetDownloadShelf creates the download shelf if it was not yet created.
+  DownloadShelf* shelf = window()->GetDownloadShelf();
+  shelf->AddDownload(download_model.release());
+  // Don't show the animation for "Save file" downloads.
+  // For non-theme extensions, we don't show the download animation.
+  // Show animation in same window as the download shelf. Download shelf
+  // may not be in the same window that initiated the download.
+  // Don't show the animation if the selected tab is not visible (i.e. the
+  // window is minimized, we're in a unit test, etc.).
+  WebContents* shelf_tab = chrome::GetActiveWebContents(shelf->browser());
+  if ((download->GetTotalBytes() > 0) &&
+      !download_crx_util::IsExtensionDownload(*download) &&
+      platform_util::IsVisible(shelf_tab->GetNativeView()) &&
+      ui::Animation::ShouldRenderRichAnimation()) {
+    DownloadStartedAnimation::Show(shelf_tab);
+  }
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Browser, content::WebContentsDelegate implementation:
 
@@ -1495,46 +1530,6 @@ int Browser::GetExtraRenderViewHeight() const {
   return window_->GetExtraRenderViewHeight();
 }
 
-void Browser::OnStartDownload(WebContents* source,
-                              content::DownloadItem* download) {
-  scoped_ptr<DownloadItemModel> download_model(new DownloadItemModel(download));
-  if (!download_model->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_model.release());
-  // Don't show the animation for "Save file" downloads.
-  // For non-theme extensions, we don't show the download animation.
-  // Show animation in same window as the download shelf. Download shelf
-  // may not be in the same window that initiated the download.
-  // Don't show the animation if the selected tab is not visible (i.e. the
-  // window is minimized, we're in a unit test, etc.).
-  WebContents* shelf_tab = chrome::GetActiveWebContents(shelf->browser());
-  if ((download->GetTotalBytes() > 0) &&
-      !download_crx_util::IsExtensionDownload(*download) &&
-      platform_util::IsVisible(shelf_tab->GetNativeView()) &&
-      ui::Animation::ShouldRenderRichAnimation()) {
-    DownloadStartedAnimation::Show(shelf_tab);
-  }
-
-  // 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_count() > 1 &&
-      !download->IsSavePackageDownload())
-    CloseContents(source);
-}
-
 void Browser::ViewSourceForTab(WebContents* source, const GURL& page_url) {
   DCHECK(source);
   chrome::ViewSource(this, source);