base: Rename discardable memory allocator interface and remove unnecessary class.

base/test/test_discardable_memory_allocator.h

+// 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.
+
+#ifndef BASE_TEST_TEST_DISCARDABLE_MEMORY_ALLOCATOR_H_
+#define BASE_TEST_TEST_DISCARDABLE_MEMORY_ALLOCATOR_H_
+
+#include "base/memory/discardable_memory_allocator.h"
+
+namespace base {
+
+class TestDiscardableMemoryAllocator : public DiscardableMemoryAllocator {

[Nico, 2015/03/16 21:55:30]

nit: StubDiscardableMemoryAllocator? Else it sounds a bit like a test. (but ok
as-is too. i'm aware it's what the old thing was called too)

[reveman, 2015/03/16 22:37:26]

hm, the idea is that it's an implementation that is useful for testing purposes.
Not testing of discardable memory but testing of code that depends on
discardable memory. "Stub" sounds like it's not a real implementation but
something that would return a fake instances of discardable memory. I prefer
TestDiscardableMemoryAllocator for that reason.

[danakj, 2015/03/16 23:03:05]

If you want the name to give more character to say its useful in tests I'd
suggest a name that describes the actual implementation. Like,
MallocDiscardableMemoryAllocator.. or.. something..

[reveman, 2015/03/17 04:09:15]

OneShotDiscardableMemoryAllocator would reflect what the current implementation
does but I still prefer to keep it as TestDiscardableMemoryAllocator. We should
be able to change this to a different implementation if we determine that to be
a more useful for testing purposes.

Anyhow, I think all this is beyond this patch, which does nothing but remove the
shmem sub string from the name.

[reveman, 2015/03/17 04:09:15]

OneShotDiscardableMemoryAllocator would reflect what the current implementation
does but I still prefer to keep it as TestDiscardableMemoryAllocator. We should
be able to change this to a different implementation if we determine that to be
more useful for testing purposes.

Anyhow, I think all this is beyond this patch, which does nothing but remove the
shmem sub-string from the name.

[reveman, 2015/03/17 14:02:41]

I added a comment to this class in latest patch.

Btw, TestDiscardableMemoryAllocator is consistent with other "for testing"
implementations in base/test such as TestSimpleTaskRunner. As well as all for
testing implementations in cc/test/.

+ public:
+  TestDiscardableMemoryAllocator();
+  ~TestDiscardableMemoryAllocator() override;
+
+  // Overridden from DiscardableMemoryAllocator:
+  scoped_ptr<DiscardableMemory> AllocateLockedDiscardableMemory(
+      size_t size) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestDiscardableMemoryAllocator);
+};
+
+}  // namespace base
+
+#endif  // BASE_TEST_TEST_DISCARDABLE_MEMORY_ALLOCATOR_H_