Purge memory before suspending timer queues when backgrounded.

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 d623c5a5d6fa57cb244877de947a0c4d7fd83b0a..5c41c9a090ec95f1d9f035612d310b13f1d81f88 100644
--- a/third_party/WebKit/public/platform/Platform.h
+++ b/third_party/WebKit/public/platform/Platform.h
@@ -669,6 +669,9 @@ class BLINK_PLATFORM_EXPORT Platform {
 
   virtual WebTrialTokenValidator* trialTokenValidator() { return nullptr; }
 
+  // Memory ------------------------------------------------------------

[bashi, 2017/02/09 07:34:58]

nit: Could you add a description?

// Requests purging memory. The platform may or may not purge memory, depending
on memory pressure.

[tasak, 2017/02/14 07:28:10]

Done.

+  virtual void requestPurgeMemory() {}
+
  protected:
   Platform();
   virtual ~Platform() {}