Bug 1475967 - Set orient="vertical" by default to the vertical Chat splitters. r=jorgk DONTBUILD

mail/components/im/content/chat-messenger.inc

@@ -175,7 +175,7 @@
                                  onclick="chatHandler.onNickClick(event);"
                                  onkeypress="chatHandler.onNicklistKeyPress(event);"/>
                   </vbox>
-                  <splitter id="logsSplitter" class="conv-chat" collapse="after"/>
+                  <splitter id="logsSplitter" class="conv-chat" collapse="after" orient="vertical"/>
                   <vbox flex="1" id="previousConversations" style="min-height: 200px;">
                     <label class="conv-logs-header-label"
                            id="participantLabel"

mail/components/im/content/imconversation.xml

@@ -27,7 +27,7 @@
             </xul:vbox>
           </xul:notificationbox>
         </xul:hbox>
-        <xul:splitter class="splitter" anonid="splitter-bottom"/>
+        <xul:splitter class="splitter" anonid="splitter-bottom" orient="vertical"/>
         <hbox anonid="convStatusContainer" class="conv-status-container" hidden="true">
           <xul:description anonid="convStatus" class="plain conv-status" crop="end" />
         </hbox>