Replace reduce-memory mode in idle notification with delayed clean-up GC.

tools/gyp/v8.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 645 matching lines @@
         '../../src/globals.h',
         '../../src/handles-inl.h',
         '../../src/handles.cc',
         '../../src/handles.h',
         '../../src/hashmap.h',
         '../../src/heap-profiler.cc',
         '../../src/heap-profiler.h',
         '../../src/heap-snapshot-generator-inl.h',
         '../../src/heap-snapshot-generator.cc',
         '../../src/heap-snapshot-generator.h',
+        '../../src/heap/memory-reducer.cc',
+        '../../src/heap/memory-reducer.h',
         '../../src/heap/gc-idle-time-handler.cc',
         '../../src/heap/gc-idle-time-handler.h',
         '../../src/heap/gc-tracer.cc',
         '../../src/heap/gc-tracer.h',
         '../../src/heap/heap-inl.h',
         '../../src/heap/heap.cc',
         '../../src/heap/heap.h',
         '../../src/heap/identity-map.cc',
         '../../src/heap/identity-map.h',
         '../../src/heap/incremental-marking-inl.h',
@@ skipping 1219 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }