Add GN build file for third_party hunspell library.

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.
+
+config("hunspell_config") {
+  defines = [
+    "HUNSPELL_STATIC",
+    "HUNSPELL_CHROME_CLIENT",
+    "USE_HUNSPELL",
+  ]
+}
+
+source_set("hunspell") {
+  sources = [
+    "google/bdict.cc",
+    "google/bdict.h",
+    "google/bdict_reader.cc",
+    "google/bdict_reader.h",
+    "google/bdict_writer.cc",
+    "google/bdict_writer.h",
+    "src/hunspell/affentry.cxx",
+    "src/hunspell/affentry.hxx",
+    "src/hunspell/affixmgr.cxx",
+    "src/hunspell/affixmgr.hxx",
+    "src/hunspell/atypes.hxx",
+    "src/hunspell/baseaffix.hxx",
+    "src/hunspell/csutil.cxx",
+    "src/hunspell/csutil.hxx",
+    "src/hunspell/dictmgr.cxx",
+    "src/hunspell/dictmgr.hxx",
+    "src/hunspell/filemgr.cxx",
+    "src/hunspell/filemgr.hxx",
+    "src/hunspell/hashmgr.cxx",
+    "src/hunspell/hashmgr.hxx",
+    "src/hunspell/htypes.hxx",
+    "src/hunspell/hunspell.cxx",
+    "src/hunspell/hunspell.h",
+    "src/hunspell/hunspell.hxx",
+    "src/hunspell/hunzip.cxx",
+    "src/hunspell/hunzip.hxx",
+    "src/hunspell/langnum.hxx",
+    "src/hunspell/phonet.cxx",
+    "src/hunspell/phonet.hxx",
+    "src/hunspell/replist.cxx",
+    "src/hunspell/replist.hxx",
+    "src/hunspell/suggestmgr.cxx",
+    "src/hunspell/suggestmgr.hxx",
+    "src/hunspell/utf_info.hxx",
+    "src/hunspell/w_char.hxx",
+    "src/parsers/textparser.cxx",
+    "src/parsers/textparser.hxx",
+  ]
+
+  direct_dependent_configs = [
+    ":hunspell_config",
+  ]
+
+  defines = [

[brettw, 2014/06/21 00:45:34]

You can delete this, direct_dependent_configs also apply to you.

[tfarina, 2014/06/21 00:53:51]

I kept for OPENOFFICEORG

+    "HUNSPELL_STATIC",
+    "HUNSPELL_CHROME_CLIENT",
+    "OPENOFFICEORG",
+  ]
+
+  deps = [
+    "//base",
+    "//third_party/icu"
+  ]
+
+  cflags = []
+
+  if (is_win) {
+    cflags += [
+      # TODO(jschuh): http://crbug.com/167187 size_t -> int
+      "/wd4267",
+    ]
+  }
+
+  if (is_posix && !is_mac) {
+    cflags += [
+      "-Wno-unused-value",
+      "-Wno-unused-variable",
+      "-Wno-write-strings",
+    ]
+  }
+
+  if (is_posix && !is_mac && !is_ios) { # gcc_version >= 48

[brettw, 2014/06/21 00:45:34]

I'd do is_linux for this (I think this is what this condition is going for). And
I think we require gcc 4.8 now so you can delete the comment.

[tfarina, 2014/06/21 00:53:51]

Done.

[tfarina, 2014/06/21 01:56:43]

Looks like it would have been better if we had went with is_posix instead:

In file included from ../../third_party/hunspell/src/hunspell/affentry.cxx:9:0:
../../third_party/hunspell/src/hunspell/affentry.hxx:30:105: error: converting
to non-pointer type 'short unsigned int' from NULL [-Werror=conversion-null]
   struct hentry *      check_twosfx(const char * word, int len, char
in_compound, const FLAG needflag = NULL);

http://build.chromium.org/p/tryserver.chromium/builders/android_chromium_gn_c...

+    cflags += [
+      # affentry.hxx has NULL as default parameter for a FLAG in two
+      # places.
+      "-Wno-conversion-null",
+    ]
+  }
+
+  if (is_clang) {
+    #"xcode_settings": {

[brettw, 2014/06/21 00:45:34]

Just delete this. In GYP this was duplicated for the XCode UI. In GN the flags
below will get used. But can you copy the comments from here to below so they're
not lost?

[tfarina, 2014/06/21 00:53:51]

Done.

+      #"WARNING_CFLAGS": [
+        # affentry.cxx has one `while ((p = nextchar(p)));` parsing loop.
+        #"-Wno-empty-body",
+        # affentry.hxx has NULL as default parameter for a FLAG in two
+        # places.
+        #"-Wno-null-conversion",
+      #]
+    #}
+    cflags += [
+      "-Wno-empty-body",
+      "-Wno-null-conversion",
+    ]
+  }
+}