DevTools: Migrate from -webkit-user-modify to contenteditable

third_party/WebKit/Source/devtools/front_end/ui/inspectorCommon.css

 /*
  * Copyright 2015 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.
  */
 
 * {
     /* This is required for correct sizing of flex items because we rely
      * on an old version of the flexbox spec.
      * Longer-term we should remove this, see crbug.com/473625 */
@@ skipping 169 matching lines @@
     padding: 1px;
     margin: -1px;
     background-color: rgba(255, 127, 0, 0.8);
 }
 
 .dimmed {
     opacity: 0.6;
 }
 
 .editing {
-    -webkit-user-select: text;
     box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.2),
                 0 2px 4px rgba(0, 0, 0, 0.2),
                 0 2px 6px rgba(0, 0, 0, 0.1);
     background-color: white;
-    -webkit-user-modify: read-write-plaintext-only;
     text-overflow: clip !important;
     padding-left: 2px;
     margin-left: -2px;
     padding-right: 2px;
     margin-right: -2px;
     margin-bottom: -1px;
     padding-bottom: 1px;
     opacity: 1.0 !important;
 }
 
@@ skipping 169 matching lines @@
     -webkit-mask-image: -webkit-image-set(url(Images/largeIcons.png) 1x, url(Images/largeIcons_2x.png) 2x);
     -webkit-mask-position: var(--spritesheet-position);
     background: white !important;
 }
 
 .force-white-icons [is=ui-icon].spritesheet-mediumicons, [is=ui-icon].force-white-icons.spritesheet-mediumicons {
     -webkit-mask-image: -webkit-image-set(url(Images/mediumIcons.png) 1x, url(Images/mediumIcons_2x.png) 2x);
     -webkit-mask-position: var(--spritesheet-position);
     background: white !important;
 }