Re-land: base: Fix registering of memory pressure listeners used when emulating discardable memory.

base/memory/discardable_memory_android.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_android.h"
 
 #include <sys/mman.h>
 #include <unistd.h>
 
 #include <limits>
@@ skipping 104 matching lines @@
   if (failed)
     DLOG(ERROR) << "Failed to unpin memory.";
   // This allows us to catch accesses to unlocked memory.
   DCHECK_EQ(0, mprotect(address, size, PROT_NONE));
   return !failed;
 }
 
 }  // namespace internal
 
 // static
+void DiscardableMemory::RegisterMemoryPressureListeners() {
+  internal::DiscardableMemoryEmulated::RegisterMemoryPressureListeners();
+}
+
+// static
+void DiscardableMemory::UnregisterMemoryPressureListeners() {
+  internal::DiscardableMemoryEmulated::UnregisterMemoryPressureListeners();
+}
+
+// static
 void DiscardableMemory::GetSupportedTypes(
     std::vector<DiscardableMemoryType>* types) {
   const DiscardableMemoryType supported_types[] = {
     DISCARDABLE_MEMORY_TYPE_ANDROID,
     DISCARDABLE_MEMORY_TYPE_EMULATED
   };
   types->assign(supported_types, supported_types + arraysize(supported_types));
 }
 
 // static
@@ skipping 24 matching lines @@
 bool DiscardableMemory::PurgeForTestingSupported() {
   return false;
 }
 
 // static
 void DiscardableMemory::PurgeForTesting() {
   NOTIMPLEMENTED();
 }
 
 }  // namespace base