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

third_party/WebKit/Source/platform/wtf/BUILD.gn

 # Copyright 2017 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.
 
 # The below is a temporary setup during the WTF migration project:
 # https://groups.google.com/a/chromium.org/d/msg/blink-dev/tLdAZCTlcAA/bYXVT8gYCAAJ
 #
 # We are moving wtf/ files to platform/wtf/ incrementally, thus, conceptually,
 # the "wtf" target in wtf/BUILD.gn is being split into two, in a way that
 # only wtf/ can refer the contents in platform/wtf/.
@@ skipping 67 matching lines @@
     "CurrentTime.cpp",
     "CurrentTime.h",
     "DynamicAnnotations.cpp",
     "DynamicAnnotations.h",
     "Forward.h",
     "GetPtr.h",
     "LeakAnnotations.h",
     "NonCopyingSort.h",
     "Noncopyable.h",
     "NotFound.h",
+    "NotNull.h",
     "Optional.h",
     "SizeAssertions.h",
     "SpinLock.h",
     "StaticConstructors.h",
     "StringExtras.h",
     "Time.h",
     "TriState.h",
     "TypeTraits.h",
     "WTFExport.h",
     "build_config.h",
@@ skipping 54 matching lines @@
     #   "text/AtomicStringCF.cpp",
     #   "text/StringImplCF.cpp",
     # ]
   }
 
   if (remove_webcore_debug_symbols) {
     configs -= [ "//build/config/compiler:default_symbols" ]
     configs += [ "//build/config/compiler:no_symbols" ]
   }
 }