Remove the object element from submittable elements

(There was a small error this also fixes in that we didn't reference a definition of the name attribute that was inclusive of the name attribute of the object element.)

Part of #6003.

source

@@ -31142,7 +31142,7 @@ interface <dfn>HTMLEmbedElement</dfn> : <span>HTMLElement</span> {
    <dd><span>Phrasing content</span>.</dd>
    <dd><span>Embedded content</span>.</dd>
    <dd>If the element has a <code data-x="attr-hyperlink-usemap">usemap</code> attribute: <span>Interactive content</span>.</dd> <!-- also when showing a plugin or a nested browsing context, but checking that statically is hard...) -->
-   <dd><span data-x="category-listed">Listed</span> and <span data-x="category-submit">submittable</span> <span>form-associated element</span>.</dd>
+   <dd><span data-x="category-listed">Listed</span> <span>form-associated element</span>.</dd>
    <dd><span>Palpable content</span>.</dd>
    <dt><span data-x="concept-element-contexts">Contexts in which this element can be used</span>:</dt>
    <dd>Where <span>embedded content</span> is expected.</dd>
@@ -42624,7 +42624,6 @@ interface <dfn>HTMLTableCellElement</dfn> : <span>HTMLElement</span> {
     <ul class="brief category-list">
      <li><code>button</code></li>
      <li><code>input</code></li>
-     <li><code>object</code></li>
      <li><code>select</code></li>
      <li><code>textarea</code></li>
      <li><span data-x="form-associated custom element">form-associated custom elements</span></li>
@@ -55161,7 +55160,7 @@ control.setSelectionRange(oldStart + prefix.length, oldEnd + prefix.length, oldD
   <p>A <span data-x="category-submit">submittable element</span> is a <dfn>candidate for constraint
   validation</dfn> except when a condition has <dfn data-x="barred from constraint validation">barred
   the element from constraint validation</dfn>. (For example, an element is <span>barred from
-  constraint validation</span> if it is an <code>object</code> element.)</p>
+  constraint validation</span> if it has a <code>datalist</code> element ancestor.)</p>
 
   <p>An element can have a <dfn>custom validity error message</dfn> defined. Initially, an element
   must have its <span>custom validity error message</span> set to the empty string. When its value
@@ -56259,9 +56258,6 @@ fur
        data-x="attr-input-type">type</code> attribute is in the <span
        data-x="attr-input-type-radio">Radio Button</span> state and whose <span
        data-x="concept-fe-checked">checkedness</span> is false.</li>
-
-       <li>The <var>field</var> element is an <code>object</code> element that is not using
-       a <span>plugin</span>.</li>
       </ul>
 
       <p>Then continue.</p>
@@ -56356,12 +56352,6 @@ fur
       </ol>
      </li>
 
-     <li><p>Otherwise, if the <var>field</var> element is an <code>object</code> element:
-     try to obtain a form submission value from the <span>plugin</span><!-- using NPAPI's
-     NPP_GetValue() entry point with the NPPVformValue variable -->, and if that is successful,
-     <span>append an entry</span> to <var>entry list</var> with <var>name</var> and the returned
-     form submission value.</p></li>
-
      <li>
       <p>Otherwise, if the <var>field</var> element is an <code>input</code> element whose <code
       data-x="attr-input-type">type</code> attribute is in the <span
@@ -119006,7 +118996,6 @@ interface <dfn>External</dfn> {
          <span data-x="Embedded content">embedded</span>;
          <span data-x="Interactive content">interactive</span>*;
          <span data-x="category-listed">listed</span>;
-         <span data-x="category-submit">submittable</span>;
          <span data-x="Form-associated element">form-associated</span>;
          <span data-x="Palpable content">palpable</span></td>
      <td><span data-x="Phrasing content">phrasing</span></td>
@@ -119974,7 +119963,6 @@ interface <dfn>External</dfn> {
      <td>
       <code>button</code>;
       <code>input</code>;
-      <code>object</code>;
       <code>select</code>;
       <code>textarea</code>;
       <span data-x="form-associated custom element">form-associated custom elements</span>