Bug 1411707 - Load findBar.css as a document stylesheet;r=paolo

Differential Revision: https://phabricator.services.mozilla.com/D5776

--HG--
extra : moz-landing-system : lando

browser/themes/osx/browser.css

@@ -230,10 +230,9 @@
 
 /* Override OSX-specific toolkit findbar button styles */
 .findbar-button {
-  background: none;
-  box-shadow: none;
+  background: none !important;
+  box-shadow: none !important;
   border: none;
-  color: inherit;
 }
 
 /* On Mac, native buttons keep their full opacity when they become disabled

toolkit/content/widgets.css

@@ -10,6 +10,7 @@
 @import url("chrome://global/skin/autocomplete.css");
 @import url("chrome://global/skin/dialog.css");
 @import url("chrome://global/skin/dropmarker.css");
+@import url("chrome://global/skin/findBar.css");
 @import url("chrome://global/skin/groupbox.css");
 @import url("chrome://global/skin/menu.css");
 @import url("chrome://global/skin/menulist.css");

toolkit/content/widgets/findbar.xml

@@ -156,10 +156,6 @@
   </binding>
 
   <binding id="findbar">
-    <resources>
-      <stylesheet src="chrome://global/skin/findBar.css"/>
-    </resources>
-
     <content hidden="true">
     <xul:hbox anonid="findbar-container" class="findbar-container" flex="1" align="center">
       <xul:hbox anonid="findbar-textbox-wrapper" align="stretch">