Add a dependency for FlatBuffers.

third_party/flatbuffers/flatc.gypi

Index: third_party/flatbuffers/flatc.gypi
diff --git a/third_party/flatbuffers/flatc.gypi b/third_party/flatbuffers/flatc.gypi
new file mode 100644
index 0000000000000000000000000000000000000000..bca0aa34a36303b8632a259a24d6c78d88f90c1d
--- /dev/null
+++ b/third_party/flatbuffers/flatc.gypi
@@ -0,0 +1,70 @@
+# Copyright (c) 2016 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.
+
+# This file is meant to be included into a target to provide a rule to invoke
+# the flatc compiler in a consistent manner.
+#
+# To use this, create a gyp target with the following form:
+# {
+#   'target_name': 'my_flatc_lib',
+#   'type': 'static_library',
+#   'sources': [
+#     'foo.fbs',
+#   ],
+#   'variables': {
+#     'flatc_out_dir': 'dir/for/my_flatc_lib'
+#   },
+#   'includes': ['path/to/this/gypi/file'],
+#   'dependencies': [
+#     '<(DEPTH)/third_party/flatbuffers/flatbuffers.gyp:flatbuffers',
+#   ]
+# }
+{
+  'variables': {
+    'flatc': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)flatc<(EXECUTABLE_SUFFIX)',
+    'cc_dir': '<(SHARED_INTERMEDIATE_DIR)/flatc_out/<(flatc_out_dir)',
+  },
+  'rules': [
+    {
+      'rule_name': 'genflatc',
+      'extension': 'fbs',
+      'inputs': [
+        '<(flatc)',
+      ],
+      'outputs': [
+        '<(cc_dir)/<(RULE_INPUT_ROOT)_generated.h',
+      ],
+      'action': [
+        '<(flatc)',
+	'-c',
+	'-o',
+	'<(cc_dir)',
+	'<(RULE_INPUT_PATH)'
+      ],
+      'message': 'Generating C++ code from <(RULE_INPUT_PATH)',
+      'process_outputs_as_sources': 1,
+    }
+  ],
+  'dependencies': [
+    '<(DEPTH)/third_party/flatbuffers/flatbuffers.gyp:flatc',
+  ],
+  'include_dirs': [
+     '<(SHARED_INTERMEDIATE_DIR)/flatc_out',
+     '<(DEPTH)',
+  ],
+  'direct_dependent_settings': {
+    'include_dirs': [
+      '<(SHARED_INTERMEDIATE_DIR)/flatc_out',
+      '<(DEPTH)',
+    ]
+  },
+  'export_dependent_settings': [
+    # The generated headers reference headers within flatbuffers,
+    # so dependencies must be able to find those headers too.
+    '<(DEPTH)/third_party/flatbuffers/flatbuffers.gyp:flatbuffers',
+  ],
+  # This target exports a hard dependency because it generates header
+  # files.
+  'hard_dependency': 1,
+}