Fix focus appearance for XUL tabs so they appear inside the tab. r=mconnor, no sr= needed

toolkit/content/widgets/tabbox.xml

@@ -450,8 +450,10 @@
   <binding id="tab" display="xul:button"
            extends="chrome://global/content/bindings/tabbox.xml#tab-base">
     <content>
-      <xul:image class="tab-icon" xbl:inherits="validate,src=image"/>
-      <xul:label class="tab-text" xbl:inherits="value=label,accesskey,crop,disabled" flex="1"/>
+      <xul:hbox flex="1" style="min-width: 1px;" align="center">
+        <xul:image class="tab-icon" xbl:inherits="validate,src=image"/>
+        <xul:label class="tab-text" xbl:inherits="value=label,accesskey,crop,disabled" flex="1"/>
+      </xul:hbox>
     </content>
     
     <implementation implements="nsIDOMXULSelectControlItemElement, nsIAccessibleProvider">

toolkit/themes/qute/global/tabbox.css

@@ -82,7 +82,7 @@ tab[selected="true"] {
   padding: 1px 6px 4px 6px;
 }
 
-tab:focus {
+tab:focus > hbox {
   -moz-outline: 1px dotted invert;
 }
 

toolkit/themes/winstripe/global/tabbox.css

@@ -83,7 +83,7 @@ tab[selected="true"]
   padding: 1px 6px 4px 6px;
 }
 
-tab:focus {
+tab:focus > hbox {
   -moz-outline: 1px dotted invert;
 }