Revert of Handle pointer-events: none in browser process hittesting.

cc/surfaces/surface_id.h

Index: cc/surfaces/surface_id.h
diff --git a/cc/surfaces/surface_id.h b/cc/surfaces/surface_id.h
index f43759c2d6ce8b9f3dc3f5ef2520748b58c6aba1..0ade6ab9135928c95d3a1e7cb9d70e4ef81e2078 100644
--- a/cc/surfaces/surface_id.h
+++ b/cc/surfaces/surface_id.h
@@ -7,8 +7,6 @@
 
 #include <stddef.h>
 #include <stdint.h>
-
-#include <functional>
 
 #include "base/containers/hash_tables.h"
 
@@ -35,12 +33,6 @@
   return a.id < b.id;
 }
 
-struct SurfaceIdHash {
-  size_t operator()(const SurfaceId& key) const {
-    return std::hash<uint64_t>()(key.id);
-  }
-};
-
 }  // namespace cc
 
 namespace BASE_HASH_NAMESPACE {