some small place fixes

source/gui/place.cpp

@@ -1737,6 +1737,9 @@ namespace nana
 				decltype(dockable_field->dockarea) del(ptr);
 			});
 
+			this->set_display(false);
+			impl_ptr_->collocate();
+
 			API::close_window(window_handle);
 		}
 	private:

source/gui/place_parts.hpp

@@ -301,7 +301,9 @@ namespace nana
 				else
 					r.height = 0;
 
-				if (!tabbar_ && panels_.size() > 0)
+				if (!tabbar_)
+				{
+					if (panels_.size() > 0)
 					{
 						tabbar_.reset(new tabbar_lite(*this));
 
@@ -325,6 +327,9 @@ namespace nana
 							tabbar_->attach(pos++, *pn.widget_ptr);
 						}
 					}
+				}
+				else
+					r.height -= 20;
 
 				auto wdg = fn(*this);