Use std::unique_ptr<> for WebTaskRunner::clone

third_party/WebKit/Source/platform/testing/TestingPlatformSupport.cpp

 /*
  * Copyright (C) 2014 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 72 matching lines @@
     {
         NOTREACHED();
     }
 
     bool runsTasksOnCurrentThread() override
     {
         NOTREACHED();
         return true;
     }
 
-    WebTaskRunner* clone() override
+    std::unique_ptr<WebTaskRunner> clone() override
     {
-        return new TestingPlatformMockWebTaskRunner(m_tasks);
+        return WTF::wrapUnique(new TestingPlatformMockWebTaskRunner(m_tasks));
     }
 
     double virtualTimeSeconds() const override
     {
         NOTREACHED();
         return 0.0;
     }
 
     double monotonicallyIncreasingVirtualTimeSeconds() const override
     {
@@ skipping 81 matching lines @@
 {
     return m_mockWebThread.get();
 }
 
 TestingPlatformMockScheduler* TestingPlatformSupportWithMockScheduler::mockWebScheduler()
 {
     return m_mockWebThread->mockWebScheduler();
 }
 
 } // namespace blink