TestingPlatformSupport: register Platform instance correctly

third_party/WebKit/Source/core/dom/IdleDeadlineTest.cpp

 // Copyright 2016 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.
 
 #include "core/dom/IdleDeadline.h"
 
 #include "platform/testing/TestingPlatformSupport.h"
 #include "public/platform/Platform.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "wtf/CurrentTime.h"
+#include "wtf/PtrUtil.h"
 
 namespace blink {
 namespace {
 
 class MockScheduler final : public TestingPlatformMockScheduler {
  public:
   MockScheduler() {}
   ~MockScheduler() override {}
   bool shouldYieldForHighPriorityWork() override { return true; }
 
@@ skipping 47 matching lines @@
   EXPECT_FLOAT_EQ(249.995, deadline->timeRemaining());
 }
 
 TEST_F(IdleDeadlineTest, deadlineInPast) {
   IdleDeadline* deadline =
       IdleDeadline::create(0.75, IdleDeadline::CallbackType::CalledWhenIdle);
   EXPECT_FLOAT_EQ(0, deadline->timeRemaining());
 }
 
 TEST_F(IdleDeadlineTest, yieldForHighPriorityWork) {
-  MockPlatform platform;
+  ScopedTestingPlatformSupport<MockPlatform> platform(
+      WTF::makeUnique<MockPlatform>());
 
   IdleDeadline* deadline =
       IdleDeadline::create(1.25, IdleDeadline::CallbackType::CalledWhenIdle);
   EXPECT_FLOAT_EQ(0, deadline->timeRemaining());
 }
 
 }  // namespace blink