Move files in wtf/ to platform/wtf/ (Part 5).

third_party/WebKit/Source/wtf/StdLibExtras.h

Index: third_party/WebKit/Source/wtf/StdLibExtras.h
diff --git a/third_party/WebKit/Source/wtf/StdLibExtras.h b/third_party/WebKit/Source/wtf/StdLibExtras.h
index d2633948b98bd909e46ffdcac39b7d20d50e03e4..b83d321a0c87af491cb69ad05be8f21334f5ac68 100644
--- a/third_party/WebKit/Source/wtf/StdLibExtras.h
+++ b/third_party/WebKit/Source/wtf/StdLibExtras.h
@@ -263,13 +263,6 @@ char (&ArrayLengthHelperFunction(T (&)[0]))[0];
 
 }  // namespace WTF
 
-// This version of placement new omits a 0 check.
-enum NotNullTag { NotNull };
-inline void* operator new(size_t, NotNullTag, void* location) {
-  DCHECK(location);
-  return location;
-}
-
 using WTF::bitwiseCast;
 using WTF::safeCast;