Implement device-ram client hints header

third_party/WebKit/public/platform/Platform.h

Index: third_party/WebKit/public/platform/Platform.h
diff --git a/third_party/WebKit/public/platform/Platform.h b/third_party/WebKit/public/platform/Platform.h
index 86c66e5bb294c1272686122a0dbc36e6c92fad1a..e34d1086b26816ea1a7abb26755983e65001d0ca 100644
--- a/third_party/WebKit/public/platform/Platform.h
+++ b/third_party/WebKit/public/platform/Platform.h
@@ -296,6 +296,9 @@ class BLINK_PLATFORM_EXPORT Platform {
   // Same as above, but always returns actual value, without any caches.
   virtual size_t ActualMemoryUsageMB() { return 0; }
 
+  // Returns the number of megabytes of physical memory on the current machine.
+  virtual size_t AmountOfPhysicalMemoryMB() { return 0; }
+
   // Return the number of of processors of the current machine.
   virtual size_t NumberOfProcessors() { return 0; }