Rewrite references to "wtf/" to "platform/wtf/" in platform/heap.

third_party/WebKit/Source/platform/heap/SelfKeepAlive.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SelfKeepAlive_h
 #define SelfKeepAlive_h
 
 #include "platform/heap/Persistent.h"
-#include "wtf/Allocator.h"
-#include "wtf/Assertions.h"
+#include "platform/wtf/Allocator.h"
+#include "platform/wtf/Assertions.h"
 
 namespace blink {
 
 // SelfKeepAlive<Object> is the idiom to use for objects that have to keep
 // themselves temporarily alive and cannot rely on there being some
 // external reference in that interval:
 //
 //  class Opener {
 //  public:
 //     ...
@@ skipping 44 matching lines @@
     m_keepAlive = self;
   }
 
   GC_PLUGIN_IGNORE("420515")
   Persistent<Self> m_keepAlive;
 };
 
 }  // namespace blink
 
 #endif  // SelfKeepAlive_h