Update from chromium https://crrev.com/301315

base/memory/discardable_memory.cc

 // Copyright 2014 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 "base/lazy_instance.h"
 #include "base/logging.h"
 
 namespace base {
 namespace {
 
 const struct TypeNamePair {
   DiscardableMemoryType type;
   const char* name;
 } kTypeNamePairs[] = {
   { DISCARDABLE_MEMORY_TYPE_ASHMEM, "ashmem" },
   { DISCARDABLE_MEMORY_TYPE_MACH, "mach" },
-  { DISCARDABLE_MEMORY_TYPE_EMULATED, "emulated" }
+  { DISCARDABLE_MEMORY_TYPE_EMULATED, "emulated" },
+  { DISCARDABLE_MEMORY_TYPE_SHMEM, "shmem" }
 };
 
 DiscardableMemoryType g_preferred_type = DISCARDABLE_MEMORY_TYPE_NONE;
 
 struct DefaultPreferredType {
   DefaultPreferredType() : value(DISCARDABLE_MEMORY_TYPE_NONE) {
     std::vector<DiscardableMemoryType> supported_types;
     DiscardableMemory::GetSupportedTypes(&supported_types);
     DCHECK(!supported_types.empty());
     value = supported_types[0];
@@ skipping 46 matching lines @@
   return g_preferred_type;
 }
 
 // static
 scoped_ptr<DiscardableMemory> DiscardableMemory::CreateLockedMemory(
     size_t size) {
   return CreateLockedMemoryWithType(GetPreferredType(), size);
 }
 
 }  // namespace base