Reland DownloadItem::Observer::OnDownloadDestroyed() replaces DownloadItem::REMOVING

chrome/browser/ui/cocoa/download/download_item_mac.mm

Index: chrome/browser/ui/cocoa/download/download_item_mac.mm
diff --git a/chrome/browser/ui/cocoa/download/download_item_mac.mm b/chrome/browser/ui/cocoa/download/download_item_mac.mm
index b5dc9b6323ceb0be7470b8bd1b8f2d8e9de44e96..a320728f2758e23d14ae665492b8e32e4e26c876 100644
--- a/chrome/browser/ui/cocoa/download/download_item_mac.mm
+++ b/chrome/browser/ui/cocoa/download/download_item_mac.mm
@@ -46,9 +46,6 @@ void DownloadItemMac::OnDownloadUpdated(content::DownloadItem* download) {
   }
 
   switch (download->GetState()) {
-    case DownloadItem::REMOVING:
-      [item_controller_ remove];  // We're deleted now!
-      break;
     case DownloadItem::COMPLETE:
       if (download->GetAutoOpened()) {
         [item_controller_ remove];  // We're deleted now!
@@ -69,6 +66,10 @@ void DownloadItemMac::OnDownloadUpdated(content::DownloadItem* download) {
   }
 }
 
+void DownloadItemMac::OnDownloadDestructed(content::DownloadItem* download) {
+  [item_controller_ remove];  // We're deleted now!
+}
+
 void DownloadItemMac::OnDownloadOpened(content::DownloadItem* download) {
   DCHECK_EQ(download, download_model_->download());
   [item_controller_ downloadWasOpened];