Standardize license headers

Many of the license headers were incorrect or corrupted. To prepare for
a check that verifies correct license headers are added to source code,
we should fix up the existing license headers to use the correct format.

The license headers that include non-Google/non-Chromium authors are
left as-is.

Change-Id: Iab9bdc41d815ac7ab07ccacf44818f3b56a75230
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2016745
Commit-Queue: Tim van der Lippe <[email protected]>
Reviewed-by: Benedikt Meurer <[email protected]>
diff --git a/front_end/settings/FrameworkBlackboxSettingsTab.js b/front_end/settings/FrameworkBlackboxSettingsTab.js
index ec6973c..fadb8d9 100644
--- a/front_end/settings/FrameworkBlackboxSettingsTab.js
+++ b/front_end/settings/FrameworkBlackboxSettingsTab.js
@@ -1,8 +1,6 @@
-/*
- * Copyright 2014 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.
- */
+// Copyright 2014 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.
 
 /**
  * @implements {UI.ListWidget.Delegate}