Don't perform a replace operation in Document.replace if there is nothing to replace. Increases performance in wrapMode if inserting many lines

lib/ace/document.js

@@ -675,6 +675,16 @@ var Document = function(text, mode) {
     },
 
     this.replace = function(range, text) {
+        // Shortcut: Nothing to replace in this case.
+        if (text.length == 0 && range.isEmpty()) {
+            return range.start;
+        } else
+        // Shortcut: If the text we want to insert is the same as it is already
+        // in the document, we don't have to replace anything.
+        if (text == this.getTextRange(range)) {
+            return range.end;
+        }
+
         this.$remove(range);
         if (text) {
             var end = this.$insert(range.start, text);