[gn] Add build file for the Zircon build.

This extra build file is identical to the original one. It will be used
while we transform the Fuchsia build into a single build, and should be
removed afterwards.

Bug: 52710
Change-Id: Ie22cef2525495f04da8e3c50b50857bc4e0e9205
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/rapidjson/+/396819
Reviewed-by: Shai Barack <shayba@google.com>
diff --git a/BUILD.zircon.gn b/BUILD.zircon.gn
new file mode 100644
index 0000000..92b7a01
--- /dev/null
+++ b/BUILD.zircon.gn
@@ -0,0 +1,86 @@
+# Copyright 2016 The Fuchsia Authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#    * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#    * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#    * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+config("rapidjson_config") {
+  include_dirs = [
+    ".",
+    "include",
+  ]
+
+  # rapidjson needs these defines to support C++11 features. These features
+  # are intentionally not autodetected by rapidjson.
+  defines = [
+    "RAPIDJSON_HAS_STDSTRING",
+    "RAPIDJSON_HAS_CXX11_RANGE_FOR",
+    "RAPIDJSON_HAS_CXX11_RVALUE_REFS",
+    "RAPIDJSON_HAS_CXX11_TYPETRAITS",
+    "RAPIDJSON_HAS_CXX11_NOEXCEPT",
+  ]
+}
+
+source_set("rapidjson") {
+  sources = [
+    "include/rapidjson/allocators.h",
+    "include/rapidjson/cursorstreamwrapper.h",
+    "include/rapidjson/document.h",
+    "include/rapidjson/encodedstream.h",
+    "include/rapidjson/encodings.h",
+    "include/rapidjson/error/en.h",
+    "include/rapidjson/error/error.h",
+    "include/rapidjson/filereadstream.h",
+    "include/rapidjson/filewritestream.h",
+    "include/rapidjson/fwd.h",
+    "include/rapidjson/internal/biginteger.h",
+    "include/rapidjson/internal/diyfp.h",
+    "include/rapidjson/internal/dtoa.h",
+    "include/rapidjson/internal/ieee754.h",
+    "include/rapidjson/internal/itoa.h",
+    "include/rapidjson/internal/meta.h",
+    "include/rapidjson/internal/pow10.h",
+    "include/rapidjson/internal/regex.h",
+    "include/rapidjson/internal/stack.h",
+    "include/rapidjson/internal/strfunc.h",
+    "include/rapidjson/internal/strtod.h",
+    "include/rapidjson/internal/swap.h",
+    "include/rapidjson/istreamwrapper.h",
+    "include/rapidjson/memorybuffer.h",
+    "include/rapidjson/memorystream.h",
+    "include/rapidjson/msinttypes/inttypes.h",
+    "include/rapidjson/msinttypes/stdint.h",
+    "include/rapidjson/ostreamwrapper.h",
+    "include/rapidjson/pointer.h",
+    "include/rapidjson/prettywriter.h",
+    "include/rapidjson/rapidjson.h",
+    "include/rapidjson/reader.h",
+    "include/rapidjson/schema.h",
+    "include/rapidjson/stream.h",
+    "include/rapidjson/stringbuffer.h",
+    "include/rapidjson/writer.h",
+  ]
+
+  public_configs = [ ":rapidjson_config" ]
+}