base: Add uncached malloc based discardable memory type.

base/memory/discardable_memory_unittest.cc

 // Copyright (c) 2013 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/memory/discardable_memory.h"
 
 #include <algorithm>
 
 #include "base/run_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 59 matching lines @@
 }
 
 // Test Lock() and Unlock() functionalities.
 TEST_P(DiscardableMemoryTest, LockAndUnLock) {
   const scoped_ptr<DiscardableMemory> memory(CreateLockedMemory(kSize));
   ASSERT_TRUE(memory);
   void* addr = memory->Memory();
   ASSERT_NE(static_cast<void*>(NULL), addr);
 
   memory->Unlock();
-  // The system should have no reason to purge discardable blocks in this brief
-  // interval, though technically speaking this might flake.
-  EXPECT_EQ(DISCARDABLE_MEMORY_LOCK_STATUS_SUCCESS, memory->Lock());
+
+  EXPECT_NE(DISCARDABLE_MEMORY_LOCK_STATUS_FAILED, memory->Lock());
   addr = memory->Memory();
   ASSERT_NE(static_cast<void*>(NULL), addr);
 
   memory->Unlock();
 }
 
 // Test delete a discardable memory while it is locked.
 TEST_P(DiscardableMemoryTest, DeleteWhileLocked) {
   const scoped_ptr<DiscardableMemory> memory(CreateLockedMemory(kSize));
   ASSERT_TRUE(memory);
@@ skipping 30 matching lines @@
   return supported_types;
 }
 
 INSTANTIATE_TEST_CASE_P(
     DiscardableMemoryTests,
     DiscardableMemoryTest,
     ::testing::ValuesIn(GetSupportedDiscardableMemoryTypes()));
 
 }  // namespace
 }  // namespace base