Implement device-ram client hints header

content/child/blink_platform_impl.cc

Index: content/child/blink_platform_impl.cc
diff --git a/content/child/blink_platform_impl.cc b/content/child/blink_platform_impl.cc
index 94eaffa8859985a83725547917291cf3e7b1e4ef..2a7ff521f7726bd650a021a5d223ecc3edd32dde 100644
--- a/content/child/blink_platform_impl.cc
+++ b/content/child/blink_platform_impl.cc
@@ -360,7 +360,9 @@ BlinkPlatformImpl::BlinkPlatformImpl()
 BlinkPlatformImpl::BlinkPlatformImpl(
     scoped_refptr<base::SingleThreadTaskRunner> main_thread_task_runner)
     : main_thread_task_runner_(main_thread_task_runner),
-      compositor_thread_(nullptr) {
+      compositor_thread_(nullptr),
+      physical_memory_mb_(
+          static_cast<size_t>(base::SysInfo::AmountOfPhysicalMemoryMB())) {
   InternalInit();
 }
 
@@ -777,6 +779,15 @@ size_t BlinkPlatformImpl::ActualMemoryUsageMB() {
   return GetMemoryUsageKB() >> 10;
 }
 
+size_t BlinkPlatformImpl::AmountOfPhysicalMemoryMB() {
+  return physical_memory_mb_;
+}
+
+void BlinkPlatformImpl::SetDevicePhysicalMemoryMBForTesting(
+    int64_t physical_memory_mb) {
+  physical_memory_mb_ = static_cast<size_t>(physical_memory_mb);
+}
+
 size_t BlinkPlatformImpl::NumberOfProcessors() {
   return static_cast<size_t>(base::SysInfo::NumberOfProcessors());
 }