--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 0c8c5e65f25b9893efbb74b76db810e5d525d2c3..2f458904689cc9a870f61a0a81eee7eb94a011c7 100644
--- a/chrome/browser/ui/browser.cc
+++ b/chrome/browser/ui/browser.cc
@@ -3391,27 +3391,30 @@ 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.
+    if (download->total_bytes() > 0) {

[cbentzel, 2011/08/10 11:54:54]

This is different behavior from before - now the two lines at the end of the
function will be called in this case. Is that OK?

[benjhayden, 2011/08/10 17:09:17]

Right, that's the bug fix part of this CL. It seems to me like we want to close
the blank temporary tab even for savepages and non-theme extensions. I quickly
tested this to check that it doesn't close non-blank tabs, but we'll see what
the browser_tests say.

+      // For non-theme extensions, we don't show the download animation.
+      if (!download->is_extension_install() ||
+          ExtensionService::IsDownloadFromMiniGallery(download->GetURL())) {

[cbentzel, 2011/08/10 11:54:54]

Same concern here.

[benjhayden, 2011/08/10 17:09:17]

Same answer.

+        // 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