Refactor bindings generation in GYP

mojo/public/tools/bindings/mojom_bindings_generator_explicit.gypi

 # Copyright 2013 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.
 
 {
-  'rules': [
+  'variables': {
+    'mojom_base_output_dir':
+      '<!(python <(DEPTH)/build/inverse_depth.py <(DEPTH))',
+    'mojom_generated_outputs': [
+      '<!@(python <(DEPTH)/mojo/public/tools/bindings/mojom_list_outputs.py --basedir <(mojom_base_output_dir) <@(mojom_files))',
+    ],
+  },
+  'actions': [
     {
-      'rule_name': '<(_target_name)_mojom_bindings_generator',
-      'extension': 'mojom',
+      'action_name': '<(_target_name)_mojom_bindings_generator',
       'variables': {
-        'mojom_base_output_dir':
-             '<!(python <(DEPTH)/build/inverse_depth.py <(DEPTH))',
         'mojom_bindings_generator':
             '<(DEPTH)/mojo/public/tools/bindings/mojom_bindings_generator.py',
         'java_out_dir': '<(PRODUCT_DIR)/java_mojo/<(_target_name)/src',
         'mojom_import_args%': [
          '-I<(DEPTH)'
         ],
       },
       'inputs': [
         '<(mojom_bindings_generator)',
         '<(DEPTH)/mojo/public/tools/bindings/generators/cpp_templates/enum_declaration.tmpl',
@@ skipping 45 matching lines @@
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/generate/module.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/generate/pack.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/generate/template_expander.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/parse/__init__.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/parse/ast.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/parse/lexer.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/parse/parser.py',
         '<(DEPTH)/mojo/public/tools/bindings/pylib/mojom/parse/translate.py',
       ],
       'outputs': [
-        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.cc',
-        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.h',
-        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom.js',
-        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT)_mojom.py',
-        '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom-internal.h',
+        '<@(mojom_generated_outputs)',
       ],
       'action': [
         'python', '<@(mojom_bindings_generator)',
-        './<(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom',
+        '<@(mojom_files)',
         '--use_chromium_bundled_pylibs',
         '-d', '<(DEPTH)',
         '<@(mojom_import_args)',
         '-o', '<(SHARED_INTERMEDIATE_DIR)',
         '--java_output_directory=<(java_out_dir)',
       ],
-      'message': 'Generating Mojo bindings from <(RULE_INPUT_DIRNAME)/<(RULE_INPUT_ROOT).mojom',
-      'process_outputs_as_sources': 1,
+      'message': 'Generating Mojo bindings from <@(mojom_files)',
     }
   ],
-  'include_dirs': [
-    '<(DEPTH)',
-    '<(SHARED_INTERMEDIATE_DIR)',
-  ],
   'direct_dependent_settings': {
-    'include_dirs': [
-      '<(DEPTH)',
-      '<(SHARED_INTERMEDIATE_DIR)',
-    ],
     'variables': {
       'generated_src_dirs': [
         '<(PRODUCT_DIR)/java_mojo/<(_target_name)/src',
       ],
     },
+    'sources': [
+      '<@(mojom_generated_outputs)',
+    ],
+    # Include paths needed to compile the generated sources into a library.
+    'include_dirs': [
+      '<(DEPTH)',
+      '<(SHARED_INTERMEDIATE_DIR)',
+    ],
+    'direct_dependent_settings': {
+      # Include paths needed to find the generated header files and their transitive
+      # dependancies when using the library.
+      'include_dirs': [
+        '<(DEPTH)',
+        '<(SHARED_INTERMEDIATE_DIR)',
+      ],
+    }
   },
   'hard_dependency': 1,
 }