--downloads-new-ui completely disables the download shelf.

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 0c456cddc5fbd8f3ad6164a9c02f89e62fec00ea..0deeb75bc8640109930fc6e4f2dc48c03a3b3c8c 100644
--- a/chrome/browser/ui/browser.cc
+++ b/chrome/browser/ui/browser.cc
@@ -3396,27 +3396,30 @@ void Browser::OnStartDownload(TabContents* source, DownloadItem* download) {
   // Open the Active Downloads ui for chromeos.
   ActiveDownloadsUI::OpenPopup(profile_);
 #else
-  // GetDownloadShelf creates the download shelf if it was not yet created.
-  DownloadShelf* shelf = window()->GetDownloadShelf();
-  shelf->AddDownload(new DownloadItemModel(download));
-
-  // Don't show the animation for "Save file" downloads.
-  if (download->total_bytes() <= 0)
-    return;
-
-  // For non-theme extensions, we don't show the download animation.
-  if (download->is_extension_install() &&
-      !ExtensionService::IsDownloadFromMiniGallery(download->GetURL()))
-    return;
-
-  // Show animation in same window as the download shelf. Download shelf
-  // may not be in the same window that initiated the download, e.g. Panels.
-  TabContents* shelf_tab = shelf->browser()->GetSelectedTabContents();
-
-  // We make this check for the case of minimized windows, unit tests, etc.
-  if (platform_util::IsVisible(shelf_tab->GetNativeView()) &&
-      ui::Animation::ShouldRenderRichAnimation()) {
-    DownloadStartedAnimation::Show(shelf_tab);
+  if (!CommandLine::ForCurrentProcess()->HasSwitch(
+        switches::kDisableDownloadShelf)) {
+    // GetDownloadShelf creates the download shelf if it was not yet created.
+    DownloadShelf* shelf = window()->GetDownloadShelf();
+    shelf->AddDownload(new DownloadItemModel(download));
+
+    // Don't show the animation for "Save file" downloads.

[ahendrickson, 2011/08/09 19:19:28]

Nit: the sense of this comment needs to be flipped.

[benjhayden, 2011/08/09 19:30:51]

Can you clarify? I thought I was careful to avoid changing intentional
functionality. It still doesn't animate for savefile downloads.

+    if (download->total_bytes() > 0) {
+      // For non-theme extensions, we don't show the download animation.
+      if (!download->is_extension_install() ||
+          ExtensionService::IsDownloadFromMiniGallery(download->GetURL())) {
+        // Show animation in same window as the download shelf. Download shelf
+        // may not be in the same window that initiated the download, e.g.
+        // Panels.
+        TabContents* shelf_tab = shelf->browser()->GetSelectedTabContents();
+
+        // We make this check for the case of minimized windows, unit tests,
+        // etc.
+        if (platform_util::IsVisible(shelf_tab->GetNativeView()) &&
+            ui::Animation::ShouldRenderRichAnimation()) {
+          DownloadStartedAnimation::Show(shelf_tab);
+        }
+      }
+    }
   }
 #endif