mode=full for the compose toolbar by default

mail/components/compose/content/messengercompose.xul

@@ -487,7 +487,7 @@
 
   <toolbar id="composeToolbar" class="toolbar-primary chromeclass-toolbar"
            toolbarname="Compose" 
-           fullscreentoolbar="true" mode="icons"
+           fullscreentoolbar="true" mode="full"
            customizable="true"
            context="toolbar-context-menu"
            defaultset="button-send,spacer,button-address,spacer,spellingButton,spacer,button-attach,button-security,spacer,button-save,spring,throbber-box">