DevTools: Extract SourcesEditor from SourcesPanel.

Source/devtools/devtools.gypi

 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #         * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #         * Redistributions in binary form must reproduce the above
@@ skipping 139 matching lines @@
             'front_end/ShortcutsScreen.js',
             'front_end/ShowMoreDataGridNode.js',
             'front_end/SidebarPane.js',
             'front_end/SidebarTreeElement.js',
             'front_end/SimpleWorkspaceProvider.js',
             'front_end/SnippetStorage.js',
             'front_end/SoftContextMenu.js',
             'front_end/SourceFrame.js',
             'front_end/SourceMap.js',
             'front_end/SourceMapping.js',
+            'front_end/SourcesEditor.js',
             'front_end/Spectrum.js',
             'front_end/SplitView.js',
             'front_end/StackView.js',
             'front_end/StatusBarButton.js',
             'front_end/StylesSourceMapping.js',
             'front_end/SuggestBox.js',
             'front_end/TabbedPane.js',
             'front_end/Target.js',
             'front_end/TempFile.js',
             'front_end/TestController.js',
@@ skipping 306 matching lines @@
             'front_end/TempStorageSharedWorker.js',
         ],
         'devtools_script_formatter_worker_js_files': [
             'front_end/CSSFormatter.js',
             'front_end/JavaScriptFormatter.js',
             'front_end/ScriptFormatterWorker.js',
             'front_end/utilities.js',
         ],
     },
 }