Do V8 GC ASAP if system memory is pressured

content/browser/memory/memory_pressure_controller_impl_browsertest.cc

 // Copyright 2015 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 "base/bind.h"
 #include "base/memory/memory_pressure_listener.h"
 #include "content/browser/memory/memory_message_filter.h"
 #include "content/browser/memory/memory_pressure_controller_impl.h"
 #include "content/common/memory_messages.h"
 #include "content/public/test/content_browser_test.h"
@@ skipping 199 matching lines @@
   SetPressureNotificationsSuppressedInAllProcessesAndWait(false);
   EXPECT_FALSE(base::MemoryPressureListener::AreNotificationsSuppressed());
   testing::Mock::VerifyAndClearExpectations(this);
 }
 
 IN_PROC_BROWSER_TEST_F(MemoryPressureControllerImplBrowserTest,
                        SimulatePressureNotificationInAllProcesses) {
   scoped_refptr<MemoryMessageFilterForTesting> filter(
       new MemoryMessageFilterForTesting);
   std::unique_ptr<base::MemoryPressureListener> listener(
-      new base::MemoryPressureListener(
+      base::MemoryPressureListener::Create(
           base::Bind(&MemoryPressureControllerImplBrowserTest::OnMemoryPressure,
                      base::Unretained(this))));
 
   NavigateToURL(shell(), GetTestUrl("", "title.html"));
 
   filter->Add();
 
   // Send a memory pressure event to the first child process. It should send a
   // pressure notification message.
   EXPECT_CALL(*filter, Send(IsPressureMessage(MEMORY_PRESSURE_LEVEL_MODERATE)))
@@ skipping 34 matching lines @@
   EXPECT_CALL(*this, OnMemoryPressure(MEMORY_PRESSURE_LEVEL_MODERATE)).Times(1);
   SimulatePressureNotificationInAllProcessesAndWait(
       MEMORY_PRESSURE_LEVEL_MODERATE);
   RunAllPendingInMessageLoop();  // Wait for the listener to run.
   testing::Mock::VerifyAndClearExpectations(this);
 
   filter->Remove();
 }
 
 }  // namespace content