Make memory-infra tests register / unregister with thread safety

content/browser/tracing/memory_tracing_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 <stdint.h>
 
 #include "base/bind.h"
 #include "base/callback_forward.h"
 #include "base/command_line.h"
 #include "base/run_loop.h"
@@ skipping 85 matching lines @@
 
     mock_dump_provider_.reset(new MockDumpProvider());
     MemoryDumpManager::GetInstance()->RegisterDumpProvider(
         mock_dump_provider_.get(), "MockDumpProvider", nullptr);
     MemoryDumpManager::GetInstance()
         ->set_dumper_registrations_ignored_for_testing(false);
     ContentBrowserTest::SetUp();
   }
 
   void TearDown() override {
-    MemoryDumpManager::GetInstance()->UnregisterDumpProvider(
-        mock_dump_provider_.get());
+    MemoryDumpManager::GetInstance()->UnregisterAndDeleteDumpProviderSoon(
+        std::move(mock_dump_provider_));
     mock_dump_provider_.reset();
     ContentBrowserTest::TearDown();
   }
 
   void EnableMemoryTracing() {
     // Re-enabling tracing could crash these tests https://crbug.com/657628 .
     if (base::trace_event::TraceLog::GetInstance()->IsEnabled()) {
       FAIL() << "Tracing seems to be already enabled. "
                 "Very likely this is because the startup tracing file "
                 "has been leaked from a previous test.";
@@ skipping 198 matching lines @@
   EXPECT_CALL(*this, OnMemoryDumpDone(_, true /* success */));
 
   EnableMemoryTracing();
   RequestGlobalDumpAndWait(false /* from_renderer_thread */,
                            MemoryDumpType::EXPLICITLY_TRIGGERED,
                            MemoryDumpLevelOfDetail::DETAILED);
   DisableTracing();
 }
 
 }  // namespace content