[DevTools] Remove Common.Event.target field.

third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js

Index: third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js
diff --git a/third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js b/third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js
index 4a669a482cca03f5281a626caf9473e27d313417..8e163c3a1bf31cd36b1d7b549848bf88fec17f38 100644
--- a/third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js
+++ b/third_party/WebKit/Source/devtools/front_end/sources/TabbedEditorContainer.js
@@ -548,19 +548,28 @@ Sources.TabbedEditorContainer = class extends Common.Object {
     }
   }
 
+  /**
+   * @param {!Common.Event} event
+   */
   _uiSourceCodeTitleChanged(event) {
-    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.target);
+    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.data);
     this._updateFileTitle(uiSourceCode);
     this._updateHistory();
   }
 
+  /**
+   * @param {!Common.Event} event
+   */
   _uiSourceCodeWorkingCopyChanged(event) {
-    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.target);
+    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.data);
     this._updateFileTitle(uiSourceCode);
   }
 
+  /**
+   * @param {!Common.Event} event
+   */
   _uiSourceCodeWorkingCopyCommitted(event) {
-    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.target);
+    var uiSourceCode = /** @type {!Workspace.UISourceCode} */ (event.data.uiSourceCode);
     this._updateFileTitle(uiSourceCode);
   }