Generate shim headers for libpng

BUG=165264

Review URL: https://codereview.chromium.org/11470020

git-svn-id: http://src.chromium.org/svn/trunk/src/build@173618 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

gyp_chromium

@@ -21,6 +21,7 @@ sys.path.insert(0, os.path.join(chrome_src, 'tools', 'gyp', 'pylib'))
 import gyp
 
 # Add paths so that pymod_do_main(...) can import files.
+sys.path.insert(1, os.path.join(chrome_src, 'tools', 'generate_shim_headers'))
 sys.path.insert(1, os.path.join(chrome_src, 'tools', 'grit'))
 sys.path.insert(1, os.path.join(chrome_src, 'chrome', 'tools', 'build'))
 sys.path.insert(1, os.path.join(chrome_src, 'native_client', 'build'))

shim_headers.gypi

@@ -0,0 +1,45 @@
+# Copyright (c) 2012 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 handle shim headers
+# in a consistent manner. To use this the following variables need to be
+# defined:
+#   headers_root_path: string: path to directory containing headers
+#   header_filenames: list: list of header file names
+
+{
+  'variables': {
+    'shim_headers_path': '<(INTERMEDIATE_DIR)/shim_headers',
+  },
+  'direct_dependent_settings': {
+    'include_dirs+': [
+      '<(shim_headers_path)',
+    ],
+  },
+  'actions': [
+    {
+      'variables': {
+        'generator_path': '<(DEPTH)/tools/generate_shim_headers/generate_shim_headers.py',
+        'generator_args': [
+          '--headers-root', '<(headers_root_path)',
+          '--output-directory', '<(shim_headers_path)',
+          '<@(header_filenames)',
+        ],
+      },
+      'action_name': 'generate_<(_target_name)_shim_headers',
+      'inputs': [
+        '<(generator_path)',
+      ],
+      'outputs': [
+        '<!@pymod_do_main(generate_shim_headers <@(generator_args) --outputs)',
+      ],
+      'action': ['python',
+                 '<(generator_path)',
+                 '<@(generator_args)',
+                 '--generate',
+      ],
+      'message': 'Generating <(_target_name) shim headers.',
+    },
+  ],
+}