Revert "Revert "Cleanup some numeric code.""

BUILD.gn

 # Copyright 2014 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("//testing/test.gni")
 import("pdfium.gni")
 
 config("pdfium_config") {
   cflags = []
   include_dirs = [ "third_party/freetype/include" ]
@@ skipping 739 matching lines @@
   ]
 }
 
 test("pdfium_unittests") {
   sources = [
     "core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp",
     "core/src/fxcrt/fx_basic_bstring_unittest.cpp",
     "core/src/fxcrt/fx_basic_memmgr_unittest.cpp",
     "core/src/fxcrt/fx_basic_wstring_unittest.cpp",
     "core/src/fxcrt/fx_bidi_unittest.cpp",
+    "core/src/fxcrt/fx_extension_unittest.cpp",
     "core/src/fxcrt/fx_system_unittest.cpp",
     "third_party/base/nonstd_unique_ptr_unittest.cpp",
   ]
   deps = [
     "//testing/gtest",
     "//testing/gtest:gtest_main",
     ":pdfium",
     ":test_support",
   ]
   include_dirs = [ "." ]
@@ skipping 42 matching lines @@
       "//v8",
       "//v8/include",
     ]
   }
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     ":pdfium_config",
     "//build/config/compiler:no_chromium_code",
   ]
 }