Resolves: tdf#66237 set layout manager the way it used to

model Frame::setLayoutManager after the Frame::impl_setPropertyValue handler
for FRAME_PROPHANDLE_LAYOUTMANAGER which used to be used before

commit b2486241
Date:   Fri Mar 22 09:24:15 2013 +0200

    fdo#46808, Convert frame::Frame to new style

i.e.

- Reference< XPropertySet > xFrameProps( m_xFrame, UNO_QUERY_THROW );
- xFrameProps->setPropertyValue( OUString( "LayoutManager" ), makeAny(Reference< XLayoutManager >()) );
+ m_xFrame->setLayoutManager( Reference< XLayoutManager >() );

Change-Id: I00f1a2cb8e4fafc6d484634619cbeaf58c603d87

framework/source/services/frame.cxx

@@ -1822,7 +1822,18 @@ void SAL_CALL Frame::setLayoutManager(const css::uno::Reference<css::uno::XInter
 {
     checkDisposed();
     SolarMutexGuard g;
-    m_xLayoutManager.set(p1, css::uno::UNO_QUERY);
+
+    css::uno::Reference<css::frame::XLayoutManager2> xOldLayoutManager = m_xLayoutManager;
+    css::uno::Reference<css::frame::XLayoutManager2> xNewLayoutManager(p1, css::uno::UNO_QUERY);
+
+    if (xOldLayoutManager != xNewLayoutManager)
+    {
+        m_xLayoutManager = xNewLayoutManager;
+        if (xOldLayoutManager.is())
+            disableLayoutManager(xOldLayoutManager);
+        if (xNewLayoutManager.is())
+            lcl_enableLayoutManager(xNewLayoutManager, this);
+    }
 }
 
 css::uno::Reference< css::beans::XPropertySetInfo > SAL_CALL Frame::getPropertySetInfo()