Allow menus to stay open during a child view's drag and drop

ui/views/controls/menu/menu_controller.cc

Index: ui/views/controls/menu/menu_controller.cc
diff --git a/ui/views/controls/menu/menu_controller.cc b/ui/views/controls/menu/menu_controller.cc
index d5b5a84e8f1b707fee0e9cf27f48c8fd0dc5d789..58fab32fce6df30deb5420f8dc5977c5b5e6ba97 100644
--- a/ui/views/controls/menu/menu_controller.cc
+++ b/ui/views/controls/menu/menu_controller.cc
@@ -793,6 +793,18 @@ void MenuController::UpdateSubmenuSelection(SubmenuView* submenu) {
   }
 }
 
+void MenuController::OnDragWillStart() {

[sky, 2014/07/14 15:19:05]

Position should match that of header.

[Devlin, 2014/07/16 16:00:45]

Whoops!  Done.

+  drag_in_progress_ = true;

[sky, 2014/07/14 15:19:05]

Before this add a DCHECK(!drag_in_progress_).

[Devlin, 2014/07/16 16:00:45]

Done.

+}
+
+void MenuController::OnDragComplete(bool should_close) {
+  drag_in_progress_ = false;

[sky, 2014/07/14 15:19:05]

And DCHECK(drag_in_progress_)

[Devlin, 2014/07/16 16:00:45]

Done.

+  if (GetActiveInstance() == this && showing_ && should_close) {

[sky, 2014/07/14 15:19:05]

move the showing_ and should_close checks first.

[Devlin, 2014/07/16 16:00:45]

Done.

+    CloseAllNestedMenus();
+    Cancel(EXIT_ALL);
+  }
+}
+
 void MenuController::OnWidgetDestroying(Widget* widget) {
   DCHECK_EQ(owner_, widget);
   owner_->RemoveObserver(this);
@@ -970,19 +982,9 @@ void MenuController::StartDrag(SubmenuView* source,
                                        &data);
   StopScrolling();
   int drag_ops = item->GetDelegate()->GetDragOperations(item);
-  drag_in_progress_ = true;
   // TODO(varunjain): Properly determine and send DRAG_EVENT_SOURCE below.
   item->GetWidget()->RunShellDrag(NULL, data, widget_loc, drag_ops,
       ui::DragDropTypes::DRAG_EVENT_SOURCE_MOUSE);
-  drag_in_progress_ = false;
-
-  if (GetActiveInstance() == this) {
-    if (showing_) {
-      // We're still showing, close all menus.
-      CloseAllNestedMenus();
-      Cancel(EXIT_ALL);
-    }  // else case, drop was on us.
-  }  // else case, someone canceled us, don't do anything
 }
 
 bool MenuController::OnKeyDown(ui::KeyboardCode key_code) {