Move NGConstraintSpace utility methods to a separate file

third_party/WebKit/Source/core/layout/BUILD.gn

 # 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.
 
 import("//third_party/WebKit/Source/core/core.gni")
 
 blink_core_sources("layout") {
   split_count = 5
 
   sources = [
@@ skipping 340 matching lines @@
     "ng/ng_macros.h",
     "ng/ng_min_max_content_size.cc",
     "ng/ng_min_max_content_size.h",
     "ng/ng_out_of_flow_layout_part.cc",
     "ng/ng_out_of_flow_layout_part.h",
     "ng/ng_physical_box_fragment.cc",
     "ng/ng_physical_box_fragment.h",
     "ng/ng_physical_fragment.cc",
     "ng/ng_physical_fragment.h",
     "ng/ng_physical_text_fragment.h",
+    "ng/ng_space_utils.cc",
+    "ng/ng_space_utils.h",
     "ng/ng_text_fragment.cc",
     "ng/ng_text_fragment.h",
     "ng/ng_text_layout_algorithm.cc",
     "ng/ng_text_layout_algorithm.h",
     "ng/ng_writing_mode.cc",
     "ng/ng_writing_mode.h",
     "shapes/BoxShape.cpp",
     "shapes/BoxShape.h",
     "shapes/PolygonShape.cpp",
     "shapes/PolygonShape.h",
@@ skipping 36 matching lines @@
       "LayoutThemeAndroid.cpp",
       "LayoutThemeAndroid.h",
     ]
   }
 
   configs += [
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     "//build/config/compiler:no_size_t_to_int_warning",
   ]
 }