Remove unused code warnings found by clang.

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")
 
 pdf_use_skia = false
 
 declare_args() {
   # On Android there's no system FreeType. On Windows and Mac, only a few
@@ skipping 232 matching lines @@
     "core/src/fpdfapi/fpdf_cmaps/Japan1/Adobe-Japan1-UCS2_4.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/EUC-H_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/EUC-V_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/Ext-RKSJ-H_2.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/Ext-RKSJ-V_2.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/H_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UCS2-HW-H_4.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UCS2-HW-V_4.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UCS2-H_4.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UCS2-V_4.cpp",
-    "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UTF16-H_5.cpp",
-    "core/src/fpdfapi/fpdf_cmaps/Japan1/UniJIS-UTF16-V_5.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/V_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Japan1/cmaps_japan1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/Adobe-Korea1-UCS2_2.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSC-EUC-H_0.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSC-EUC-V_0.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSCms-UHC-HW-H_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSCms-UHC-HW-V_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSCms-UHC-H_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSCms-UHC-V_1.cpp",
     "core/src/fpdfapi/fpdf_cmaps/Korea1/KSCpc-EUC-H_0.cpp",
@@ skipping 519 matching lines @@
     "//v8",
     "//v8/include",
     "."
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     ":pdfium_config",
     "//build/config/compiler:no_chromium_code",
   ]
 }