Add a full QWERTY layout.

ui/keyboard/resources/elements/kb-key-sequence.html

 <!--
   -- Copyright 2013 The Chromium Authors. All rights reserved.
   -- Use of this source code is governed by a BSD-style license that can be
   -- found in the LICENSE file.
   -->
 
-<polymer-element name="kb-key-sequence" attributes="keys hintTexts keyCodes">
+<polymer-element name="kb-key-sequence"
+    attributes="keys hintTexts keyCodes invert">
   <template>
     <style>
       @host {
         * {
           display: none;
         }
       }
     </style>
     <kb-key-codes id="keyCodeMetadata"></kb-key-codes>
   </template>
@@ skipping 16 matching lines @@
              console.error('keys and keyCodes do not match');
             return;
           }
           var replacement = document.createDocumentFragment();
           for (var i = 0; i < newKeys.length; i++) {
             var key = document.createElement('kb-key');
             key.innerText = newKeys[i];
             key.accents = newKeys[i];
             if (newHintTexts)
               key.hintText = newHintTexts[i];
+            var keyCodeIndex = keyCodes[i];
+
+            if (this.invert) {
+              key.invert = true;
+              key.char = newKeys[i];
+              keyCodeIndex = key.hintText;
+            }
             var state = this.$.keyCodeMetadata.GetKeyCodeAndModifiers(
-                keyCodes[i]);
+                keyCodeIndex);
             if (state) {
               key.keyCode = state.keyCode;
               key.shiftModifier = state.shiftModifier;
             }
             replacement.appendChild(key);
           }
           result = replacement;
         }
         return result;
       }
     });
   </script>
 </polymer-element>