downloads: clicking "remove" on chrome://downloads should also hide shelf item.

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

Index: chrome/browser/ui/cocoa/download/download_shelf_controller.mm
diff --git a/chrome/browser/ui/cocoa/download/download_shelf_controller.mm b/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
index ebebb03f18c96560117ed7c28b07ca535c560912..29b6398c091401c2fa3569578719eaf8d389240a 100644
--- a/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
+++ b/chrome/browser/ui/cocoa/download/download_shelf_controller.mm
@@ -309,6 +309,17 @@ const NSSize kHoverCloseButtonDefaultSize = { 18, 18 };
   [self add:controller.get()];
 }
 
+- (void)removeDownloadItem:(DownloadItem*)downloadItem {
+  for (NSUInteger i = 0; i < [downloadItemControllers_ count]; ++i) {
+    DownloadItemController* itemController =
+        [downloadItemControllers_ objectAtIndex:i];
+    if ([itemController download] == downloadItem) {
+      [self remove:itemController];
+      return;
+    }
+  }
+}
+
 - (void)add:(DownloadItemController*)controller {
   DCHECK([NSThread isMainThread]);
   [self cancelAutoClose];