Original patch from issue 570048

chrome/renderer/resources/json_schema.js

 // Copyright (c) 2009 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.
 
 // -----------------------------------------------------------------------------
 // NOTE: If you change this file you need to touch renderer_resources.grd to
 // have your change take effect.
 // -----------------------------------------------------------------------------
 
 //==============================================================================
@@ skipping 387 matching lines @@
     instance, schema, path) {
 
   // Forbid NaN, +Infinity, and -Infinity.  Our APIs don't use them, and
   // JSON serialization encodes them as 'null'.  Re-evaluate supporting
   // them if we add an API that could reasonably take them as a parameter.
   if (isNaN(instance) ||
       instance == Number.POSITIVE_INFINITY ||
       instance == Number.NEGATIVE_INFINITY )
     this.addError(path, "numberFiniteNotNan", [instance]);
 
-  if (schema.minimum && instance < schema.minimum)
+  if (typeof schema.minimum != 'undefined' && instance < schema.minimum)
     this.addError(path, "numberMinValue", [schema.minimum]);
 
-  if (schema.maximum && instance > schema.maximum)
+  if (typeof schema.maximum != 'undefined' && instance > schema.maximum)
     this.addError(path, "numberMaxValue", [schema.maximum]);
 
-  if (schema.maxDecimal && instance * Math.pow(10, schema.maxDecimal) % 1)
+  if (typeof schema.maxDecimal != 'undefined' &&
+      instance * Math.pow(10, schema.maxDecimal) % 1) {
     this.addError(path, "numberMaxDecimal", [schema.maxDecimal]);
+  }
 };
 
 /**
  * Validates the primitive type of an instance and populates the errors
  * property. Returns true if the instance validates, false otherwise.
  */
 chromeHidden.JSONSchemaValidator.prototype.validateType = function(
     instance, schema, path) {
   var actualType = chromeHidden.JSONSchemaValidator.getType(instance);
   if (schema.type != actualType && !(schema.type == "number" &&
@@ skipping 12 matching lines @@
  */
 chromeHidden.JSONSchemaValidator.prototype.addError = function(
     path, key, replacements) {
   this.errors.push({
     path: path,
     message: chromeHidden.JSONSchemaValidator.formatError(key, replacements)
   });
 };
 
 })();