Add an implementation path option to json_schema_compiler

build/json_schema_compile.gypi

 # 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.
 
 {
   'variables': {
     # When including this gypi, the following variables must be set:
     #   schema_files: a list of json or IDL files that comprise the api model.
     #   cc_dir: path to generated files
     #   root_namespace: the C++ namespace that all generated files go under
     # Functions and namespaces can be excluded by setting "nocompile" to true.
+    # The default root path of API implementation sources is
+    # chrome/browser/extensions/api and can be overridden by setting "impl_dir".
     'api_gen_dir': '<(DEPTH)/tools/json_schema_compiler',
     'api_gen': '<(api_gen_dir)/compiler.py',
+    'impl_dir%': 'chrome/browser/extensions/api',
   },
   'rules': [
     {
       'rule_name': 'genapi',
       'msvs_external_rule': 1,
       'extension': 'json',
       'inputs': [
         '<(api_gen_dir)/cc_generator.py',
         '<(api_gen_dir)/code.py',
         '<(api_gen_dir)/compiler.py',
@@ skipping 16 matching lines @@
         '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_ROOT).h',
       ],
       'action': [
         'python',
         '<(api_gen)',
         '<(RULE_INPUT_PATH)',
         '--root=<(DEPTH)',
         '--destdir=<(SHARED_INTERMEDIATE_DIR)',
         '--namespace=<(root_namespace)',
         '--generator=cpp',
+        '--impl-dir=<(impl_dir)'
       ],
       'message': 'Generating C++ code from <(RULE_INPUT_PATH) json files',
       'process_outputs_as_sources': 1,
     },
     {
       'rule_name': 'genapi_idl',
       'msvs_external_rule': 1,
       'extension': 'idl',
       'inputs': [
         '<(api_gen_dir)/cc_generator.py',
@@ skipping 18 matching lines @@
         '<(SHARED_INTERMEDIATE_DIR)/<(cc_dir)/<(RULE_INPUT_ROOT).h',
       ],
       'action': [
         'python',
         '<(api_gen)',
         '<(RULE_INPUT_PATH)',
         '--root=<(DEPTH)',
         '--destdir=<(SHARED_INTERMEDIATE_DIR)',
         '--namespace=<(root_namespace)',
         '--generator=cpp',
+        '--impl-dir=<(impl_dir)'
       ],
       'message': 'Generating C++ code from <(RULE_INPUT_PATH) IDL files',
       'process_outputs_as_sources': 1,
     },
   ],
   'include_dirs': [
     '<(SHARED_INTERMEDIATE_DIR)',
     '<(DEPTH)',
   ],
   'dependencies':[
     '<(DEPTH)/tools/json_schema_compiler/api_gen_util.gyp:api_gen_util',
   ],
   'direct_dependent_settings': {
     'include_dirs': [
       '<(SHARED_INTERMEDIATE_DIR)',
     ]
   },
   # This target exports a hard dependency because it generates header
   # files.
   'hard_dependency': 1,
 }