Fix override of property for a specific widgetMode when already defined for widgetMode="any"

The following code does not work, tested on nuxeo-dm-5.5-I20111104_1115-tomcat.
Indeed, if the widget mode is "view", then the effective value for the "mode" property is "edit", and not "view" as we could expect it.

<widget name="carac_allergenes" type="layout">
...
<properties widgetMode="any">
<property name="name">carac_allergenes</property>
<property name="mode">edit</property>
</properties>
<properties widgetMode="view">
<property name="mode">view</property>
</properties>
</widget>

As a workaround, the following code works :

<widget name="carac_allergenes" type="layout">
...
<properties widgetMode="any">
<property name="name">carac_allergenes</property>
</properties>
<properties widgetMode="view">
<property name="mode">view</property>
</properties>
<properties widgetMode="edit">
<property name="mode">edit</property>
</properties>
</widget>

Thanks.