Avoid unnecessary wtf/text/WTFString.h includes in platform/heap/

third_party/WebKit/Source/platform/PurgeableVector.cpp

 /*
  * Copyright (C) 2014 Google Inc. 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
@@ skipping 19 matching lines @@
 
 #include "config.h"
 #include "platform/PurgeableVector.h"
 
 #include "public/platform/Platform.h"
 #include "public/platform/WebDiscardableMemory.h"
 #include "public/platform/WebProcessMemoryDump.h"
 #include "wtf/Assertions.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
+#include "wtf/text/WTFString.h"
 
 #include <cstring>
 
 namespace blink {
 
 // WebDiscardableMemory allocations are expensive and page-grained. We only use
 // them when there's a reasonable amount of memory to be saved by the OS
 // discarding the memory.
 static const size_t minimumDiscardableAllocationSize = 4 * 4096;
 
@@ skipping 217 matching lines @@
     // fragmentation.
     // Since the page size is only used below to minimize fragmentation it's still safe to use it
     // even if it gets out of sync (e.g. due to the use of huge pages).
     const size_t kPageSize = 4096;
     newCapacity = (newCapacity + kPageSize - 1) & ~(kPageSize - 1);
 
     return std::max(capacity, newCapacity); // Overflow check.
 }
 
 } // namespace blink