Implement device-ram client hints header

third_party/WebKit/Source/platform/MemoryCoordinator.cpp

 // 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 "platform/MemoryCoordinator.h"
 
 #include "base/sys_info.h"
 #include "platform/fonts/FontCache.h"
 #include "platform/graphics/ImageDecodingStore.h"
 #include "platform/instrumentation/tracing/TraceEvent.h"
 #include "platform/wtf/allocator/Partitions.h"
 
 namespace blink {
 
 // static
 bool MemoryCoordinator::is_low_end_device_ = false;
+int64_t MemoryCoordinator::physical_memory_mb_ = 0;
 
 // static
 bool MemoryCoordinator::IsLowEndDevice() {
   return is_low_end_device_;
 }
 
 // static
+int64_t MemoryCoordinator::GetPhysicalMemoryMB() {
+  return physical_memory_mb_;
+}
+
+// static
+void MemoryCoordinator::SetPhysicalMemoryMBForTesting(
+    int64_t physical_memory_mb) {
+  physical_memory_mb_ = physical_memory_mb;
+}
+
+// static
 void MemoryCoordinator::Initialize() {
   is_low_end_device_ = ::base::SysInfo::IsLowEndDevice();
+  physical_memory_mb_ = ::base::SysInfo::AmountOfPhysicalMemoryMB();
 }
 
 // static
 void MemoryCoordinator::SetIsLowEndDeviceForTesting(bool is_low_end_device) {
   is_low_end_device_ = is_low_end_device;
 }
 
 // static
 MemoryCoordinator& MemoryCoordinator::Instance() {
   DEFINE_STATIC_LOCAL(Persistent<MemoryCoordinator>, external,
@@ skipping 48 matching lines @@
   // MemoryCoordinatorClients rather than clearing caches here.
   ImageDecodingStore::Instance().Clear();
   FontCache::GetFontCache()->Invalidate();
 }
 
 DEFINE_TRACE(MemoryCoordinator) {
   visitor->Trace(clients_);
 }
 
 }  // namespace blink