set mnemonic widgets for background page

Change-Id: I977d8d7f1d14ea6616cf4dc3dc49d201804b7c39

cui/source/tabpages/backgrnd.cxx

@@ -1530,6 +1530,7 @@ void SvxBackgroundTabPage::ShowTblControl()
     m_pTblLBox->SelectEntryPos(0);
     m_pTblDesc->Show();
     m_pTblLBox->Show();
+    m_pTblDesc->set_mnemonic_widget(m_pTblLBox);
 }
 
 //-----------------------------------------------------------------------
@@ -1538,10 +1539,11 @@ void SvxBackgroundTabPage::ShowParaControl(sal_Bool bCharOnly)
 {
     m_pParaLBox->SetSelectHdl(HDL(ParaDestinationHdl_Impl));
     m_pParaLBox->SelectEntryPos(0);
-    if(!bCharOnly)
+    if (!bCharOnly)
     {
         m_pTblDesc->Show();
         m_pParaLBox->Show();
+        m_pTblDesc->set_mnemonic_widget(m_pParaLBox);
     }
     m_pParaLBox->SetData(m_pParaLBox); // here it can be recognized that this mode is turned on
 }

cui/uiconfig/ui/backgroundpage.ui

@@ -27,6 +27,7 @@
             <property name="no_show_all">True</property>
             <property name="label" translatable="yes">A_s</property>
             <property name="use_underline">True</property>
+            <property name="mnemonic_widget">selectlb</property>
           </object>
           <packing>
             <property name="left_attach">0</property>
@@ -173,6 +174,7 @@
                         <property name="no_show_all">True</property>
                         <property name="label" translatable="yes">_Transparency</property>
                         <property name="use_underline">True</property>
+                        <property name="mnemonic_widget">transparencymf:0%</property>
                       </object>
                       <packing>
                         <property name="left_attach">0</property>