Reland: Add MemoryCoordinatorClient

third_party/WebKit/public/platform/WebMemoryCoordinator.h

Index: third_party/WebKit/public/platform/WebMemoryCoordinator.h
diff --git a/third_party/WebKit/public/web/WebMemoryCoordinator.h b/third_party/WebKit/public/platform/WebMemoryCoordinator.h
similarity index 63%
rename from third_party/WebKit/public/web/WebMemoryCoordinator.h
rename to third_party/WebKit/public/platform/WebMemoryCoordinator.h
index 306b961c12f4523ff7079eacaa6deee5320a9b03..e0a80687c13f331ff59758f47314d6d380d76d13 100644
--- a/third_party/WebKit/public/web/WebMemoryCoordinator.h
+++ b/third_party/WebKit/public/platform/WebMemoryCoordinator.h
@@ -13,7 +13,12 @@ namespace blink {
 class WebMemoryCoordinator {
 public:
     // Called when a memory pressure notification is received.
-    BLINK_EXPORT static void onMemoryPressure(WebMemoryPressureLevel);
+    // TODO(bashi): Deprecating. Remove this when MemoryPressureListener is
+    // gone.
+    BLINK_PLATFORM_EXPORT static void onMemoryPressure(WebMemoryPressureLevel);
+
+    // Called when Blink should purge caches.
+    BLINK_PLATFORM_EXPORT static void purgeMemory();
 };
 
 } // namespace blink