DevTools: one objectValue css for console instead of per message

Before, each visible console message created a 'objectValue.css'
style tag, resulting in a lot of duplicate rules
( https://imgur.com/a/cT1QX )

This CL replaces per-message style tags with a single one for
ConsoleView, since messages only appear within ConsoleView.

Bug: none
Change-Id: I91b4d4ac766e2d6b29f5d68068c9d7a9d850c16a
Reviewed-on: https://chromium-review.googlesource.com/879848Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Erik Luo <luoe@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533794}

third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js

@@ -36,6 +36,7 @@ Console.ConsoleView = class extends UI.VBox {
     super();
     this.setMinimumSize(0, 35);
     this.registerRequiredCSS('console/consoleView.css');
+    this.registerRequiredCSS('object_ui/objectValue.css');
 
     this._searchableView = new UI.SearchableView(this);
     this._searchableView.element.classList.add('console-searchable-view');

third_party/WebKit/Source/devtools/front_end/console/ConsoleViewMessage.js

@@ -114,9 +114,7 @@ Console.ConsoleViewMessage = class {
    * @return {!Element}
    */
   _buildTableMessage() {
-    var formattedMessage = createElement('span');
-    UI.appendStyle(formattedMessage, 'object_ui/objectValue.css');
-    formattedMessage.className = 'source-code';
+    var formattedMessage = createElementWithClass('span', 'source-code');
     var anchorElement = this._buildMessageAnchor();
     if (anchorElement)
       formattedMessage.appendChild(anchorElement);
@@ -271,10 +269,7 @@ Console.ConsoleViewMessage = class {
     }
     messageElement.classList.add('console-message-text');
 
-    var formattedMessage = createElement('span');
-    UI.appendStyle(formattedMessage, 'object_ui/objectValue.css');
-    formattedMessage.className = 'source-code';
-
+    var formattedMessage = createElementWithClass('span', 'source-code');
     var anchorElement = this._buildMessageAnchor();
     if (anchorElement)
       formattedMessage.appendChild(anchorElement);