title: Razor validation firing without [required] attribute
body: <p>Here is my model</p>
  
  <pre><code>public class SchoolUser
  {
      public int schoolId { get; set; }
  
      public int contact1UserId { get; set; }
  
      public IEnumerable&lt;DataLayer.salutations&gt; Salutations { get; set; }
  
      public int departmentId { get; set; }
  
      public IEnumerable&lt;DataLayer.departments&gt; Departments { get; set; }
  
      [Required]
      public int roleId { get; set; }
  
      public IEnumerable&lt;DataLayer.rolesView&gt; roles { get; set; }
  </code></pre>
  
  <p>Here is my razor code for creating dropdown for deptartmentid view </p>
  
  <pre><code>                &lt;div style="width:75%; display:inline-block; margin-left:5px;"&gt;
                      @Html.DropDownListFor(model =&gt; model.departmentId, new SelectList(Model.Departments, "deptId", "description"), "")
                      @Html.ValidationMessageFor(model =&gt; model.departmentId)
                  &lt;/div&gt;                    
  </code></pre>
  
  <p>What confuses us to no end, razor validation complains when no dept is chosen. But the school model had no [required] attribute.</p>
  
  <p><strong>"The departmentId field is required."</strong></p>
  
  <p>Looking at page source I see </p>
  
  <pre><code> &lt;select data-val="true" data-val-number="The field departmentId must be a number." data-val-required="The departmentId field is required." id="departmentId" name="departmentId"&gt;&lt;option value=""&gt;&lt;/option&gt;
  &lt;option value="30"&gt;English&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>For some reason, the razor view engine has 'decided' to require this field to be populated even though the model has no [required] or other constraining attribute.</p>