DevTools: Replace multiline InplaceEditor with CodeMirrorTextEditor

third_party/WebKit/Source/devtools/front_end/source_frame/SourcesTextEditor.js

 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 /**
  * @unrestricted
  */
 SourceFrame.SourcesTextEditor = class extends TextEditor.CodeMirrorTextEditor {
   /**
    * @param {!SourceFrame.SourcesTextEditorDelegate} delegate
    */
   constructor(delegate) {
     super({
       lineNumbers: true,
       lineWrapping: false,
       bracketMatchingSetting: Common.moduleSetting('textEditorBracketMatching'),
+      padBottom: true
     });
 
     this.codeMirror().addKeyMap({'Enter': 'smartNewlineAndIndent', 'Esc': 'sourcesDismiss'});
 
     this._delegate = delegate;
 
     this.codeMirror().on('changes', this._fireTextChanged.bind(this));
     this.codeMirror().on('cursorActivity', this._cursorActivity.bind(this));
     this.codeMirror().on('gutterClick', this._gutterClick.bind(this));
     this.codeMirror().on('scroll', this._scroll.bind(this));
@@ skipping 844 matching lines @@
    */
   _setHighlighter(highlighter, selectionStart) {
     var overlayMode = {token: highlighter};
     this._codeMirror.addOverlay(overlayMode);
     this._highlightDescriptor = {overlay: overlayMode, selectionStart: selectionStart};
   }
 };
 
 SourceFrame.SourcesTextEditor.LinesToScanForIndentationGuessing = 1000;
 SourceFrame.SourcesTextEditor.MaximumNumberOfWhitespacesPerSingleSpan = 16;