Make GYP and GN build consistent for third_party targets

third_party/BUILD.gn

 # Copyright 2014 PDFium 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("../pdfium.gni")
 
 group("third_party") {
   deps = [
     ":bigint",
     ":fx_freetype",
@@ skipping 310 matching lines @@
     "libpng16/pngstruct.h",
     "libpng16/pngtrans.c",
     "libpng16/pngwio.c",
     "libpng16/pngwrite.c",
     "libpng16/pngwtran.c",
     "libpng16/pngwutil.c",
   ]
 }
 
 if (pdf_enable_xfa) {
-  config("fx_tiff_warnings") {
-    visibility = [ ":*" ]
-    if (is_win) {
-      cflags = [
-        "/wd4005",  # Macro redefinition for 'WIN32_LEAN_AND_MEAN'.
-      ]
-    }
-  }
   source_set("fx_tiff") {
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
       "../:pdfium_config",
-
-      ":fx_tiff_warnings",
     ]
     deps = [
       "//third_party:jpeg",
     ]
+    defines -= [

[Lei Zhang, 2016/05/09 21:03:22]

The third_party.gyp version has this inside an OS=="win" conditional. Can we
make the two consistent? Probably doesn't matter either way.

[Wei Li, 2016/05/09 21:33:22]

Sure, changed the gyp file as the condition is not needed.

[Lei Zhang, 2016/05/09 21:43:54]

I should also mention this doesn't work in GN:

Generating files...
ERROR at //third_party/BUILD.gn:340:5: Undefined variable for -=.
    defines -= [
    ^------
I don't have something with this name in scope now.

[Wei Li, 2016/05/09 22:35:47]

Turns out the condition is still needed. Changed to the gn way to handle this.

+      # Need to undefine the macro since it is redefined in
+      # tif_ojpeg.c and tif_jpeg.c.
+      'WIN32_LEAN_AND_MEAN',

[Lei Zhang, 2016/05/09 21:43:54]

Needs to be double quotes.

[Wei Li, 2016/05/09 22:35:47]

Acknowledged.

+    ],

[Lei Zhang, 2016/05/09 21:43:54]

No trailing comma.

[Wei Li, 2016/05/09 22:35:47]

Acknowledged.

     sources = [
       "libtiff/tif_aux.c",
       "libtiff/tif_close.c",
       "libtiff/tif_codec.c",
       "libtiff/tif_color.c",
       "libtiff/tif_compress.c",
       "libtiff/tif_dir.c",
       "libtiff/tif_dirinfo.c",
       "libtiff/tif_dirread.c",
       "libtiff/tif_dirwrite.c",
@@ skipping 74 matching lines @@
   sources = [
     "base/logging.h",
     "base/macros.h",
     "base/numerics/safe_conversions.h",
     "base/numerics/safe_conversions_impl.h",
     "base/numerics/safe_math.h",
     "base/numerics/safe_math_impl.h",
     "base/stl_util.h",
   ]
 }