title: Grails Constraints are not creating view validation errors after move from 2.3.4 to 2.3.5
body: <p>I am fairly new to GRAILS, using 2.3.5.</p>
  
  <p>I have a fairly simple domain object:</p>
  
  <pre><code>class Product {
     String name
     ProductType type
     ProductType subtype
     String desc
  
     static belongsTo = [organization: Organization]
     static constraints = {
       name blank: false
       type blank: false
       subtype blank: false
       desc nullable: true, maxSize:1000
     }
  }
  </code></pre>
  
  <p>I then have the following for the controller save action:</p>
  
  <pre><code> def save(Product productInstance) {
  
      if(!productInstance.save()) {
          respond productInstance.errors, view: 'create'
      } else {
          request.withFormat {
              form {
                  flash.message = "Product '${productInstance.name}' was created successfully!"
              redirect controller: 'product', action: 'index'
              }
              '*' {respond productInstance, [status: CREATED]}
          }
      }
  }
  </code></pre>
  
  <p>No matter what constraint I use, I get the expected result, which is the DB insert will not succeed, but I don't get the errors trapped and sent back to the "create" view like I expect, I get the error.gsp page with a SERVER 500 Error stating the exception and the failed query.  Is there a setting I am missing?  I am just using the H2 DB.  </p>