b=338874. Safe browsing alert not exposed to screenreader. Patch by pilgrim@gmail.com. r=tony, sr=darin

browser/components/safebrowsing/content/phishing-afterload-displayer.js

@@ -505,6 +505,7 @@ PROT_PhishMsgDisplayerCanvas.prototype.showMessage_ = function() {
   // 4. unhide stack contents
   // 5. display to the canvas
   // 6. unhide the warning message
+  // 7. focus the warning message
 
   // (1)
   // We add the canvas dynamically and remove it when we're done because
@@ -563,6 +564,9 @@ PROT_PhishMsgDisplayerCanvas.prototype.showMessage_ = function() {
   tail.hidden = false;
   tail.style.display = "block";
   this.adjustLocation_(message, tail, refElement);
+
+  // (7)
+  this.doc_.getElementById(this.messageContentId_).focus();
 }
 
 /**

browser/components/safebrowsing/content/warning-overlay.xul

@@ -34,7 +34,11 @@
       <!-- This is the main warning area -->
 
       <vbox id="safebrowsing-palm-message-content" 
-      class="safebrowsing-palm-fixed-width safebrowsing-palm-message-bubble">
+      class="safebrowsing-palm-fixed-width safebrowsing-palm-message-bubble"
+      style="-moz-user-focus: normal"
+      xmlns:x2="http://www.w3.org/TR/xhtml2"
+      xmlns:wairole="http://www.w3.org/2005/01/wai-rdf/GUIRoleTaxonomy#"
+      x2:role="wairole:alert">
 
         <!-- Top line -->