Updating JSON Schema Compiler to add description field to schemas.

tools/json_schema_compiler/test/font_settings.json

 // Copyright (c) 2012 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.
 
 [
   {
     "namespace": "fontSettings",
+    "description": "The fontSettings API.",
     "types": [
       {
         "id": "FontName",
         "type": "object",
         "description": "Represents a font name.",
         "properties": {
           "fontName": {
             "type": "string",
             "description": "The font name."
           },
@@ skipping 523 matching lines @@
                 "$ref": "LevelOfControl",
                 "description": "The level of control this extension has over the setting."
               }
             }
           }
         ]
       }
     ]
   }
 ]