Don't verify that typeof form.submit is function before replacing it

That's apparently not a reliable thing to test for.

Issue #927

Author: marijnh

lib/codemirror.js

@@ -2236,15 +2236,13 @@ window.CodeMirror = (function() {
     if (textarea.form) {
       // Deplorable hack to make the submit method do the right thing.
       var rmSubmit = connect(textarea.form, "submit", save, true);
-      if (typeof textarea.form.submit == "function") {
-        var realSubmit = textarea.form.submit;
-        textarea.form.submit = function wrappedSubmit() {
-          save();
-          textarea.form.submit = realSubmit;
-          textarea.form.submit();
-          textarea.form.submit = wrappedSubmit;
-        };
-      }
+      var realSubmit = textarea.form.submit;
+      textarea.form.submit = function wrappedSubmit() {
+        save();
+        textarea.form.submit = realSubmit;
+        textarea.form.submit();
+        textarea.form.submit = wrappedSubmit;
+      };
     }
 
     textarea.style.display = "none";