Mojo: Simplify typemap usage.

mojo/mojom_bindings_generator.gypi

Index: mojo/mojom_bindings_generator.gypi
diff --git a/mojo/mojom_bindings_generator.gypi b/mojo/mojom_bindings_generator.gypi
index bcf98b229e94cf9eebca7df57e63d3ad8ec32a58..bcd10a8f755eb63049e6830092fa12f1ead67008 100644
--- a/mojo/mojom_bindings_generator.gypi
+++ b/mojo/mojom_bindings_generator.gypi
@@ -8,24 +8,18 @@
   ],
   'variables': {
     'variables': {
-      'mojom_typemap_dependencies%': [],
-      'mojom_typemaps%': [],
       'mojom_variant%': 'none',
       'for_blink%': 'false',
     },
-    'mojom_typemap_dependencies%': ['<@(mojom_typemap_dependencies)'],
-    'mojom_typemaps%': ['<@(mojom_typemaps)'],
     'mojom_variant%': '<(mojom_variant)',
+    'mojom_typemaps%': [],
     'for_blink%': '<(for_blink)',
     '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) --variant <(mojom_variant) <@(_sources))',
     ],
-    'mojom_generator_typemap_args': [
-      '<!@(python <(DEPTH)/mojo/public/tools/bindings/mojom_get_generator_typemap_args.py <@(mojom_typemaps))',
-    ],
-    'mojom_extra_generator_args%': [],
+    'mojom_typemap_file': '<(SHARED_INTERMEDIATE_DIR)/<(mojom_base_output_dir)/<(_target_name)_type_mappings',
     'conditions': [
       ['mojom_variant=="none"', {
         'mojom_output_languages%': 'c++,javascript,java',
@@ -62,7 +56,23 @@
       ],
       'inputs': [ '<@(_sources)' ],
       'outputs': [ '<(stamp_filename)' ],
-    }
+    },
+    {
+      'variables': {
+        'output': '<(mojom_typemap_file)',

[yzshen1, 2016/04/08 19:58:25]

nit: I feel that the name is pretty similar to mojom_typemaps. Does it make
sense to name it something like generated_typemap_file?

[Sam McNally, 2016/04/11 04:40:27]

Done.

+      },
+      'action_name': '<(_target_name)_type_mappings',
+      'action': [
+        'python', '<(DEPTH)/mojo/public/tools/bindings/generate_type_mappings.py',
+        '--output',
+        '<(output)',
+        '<!@(python <(DEPTH)/mojo/public/tools/bindings/format_typemap_generator_args.py <@(mojom_typemaps))',
+      ],
+      'inputs':[
+        '<(DEPTH)/mojo/public/tools/bindings/generate_type_mappings.py',

[yzshen1, 2016/04/08 19:58:25]

Do we need to add those files listed in mojom_typemaps as input too?

[Sam McNally, 2016/04/11 04:40:27]

No, they're only used by GYP to generate the command line.

[yzshen1, 2016/04/11 16:02:55]

(Sorry if I misunderstand how/when an action is triggered.) If "mojom_typemaps"
are not listed as "inputs", when those files' contents are changed, will GYP
know that this target needs to be re-compiled?

[Sam McNally, 2016/04/12 07:54:32]

Those files are only used when GYP runs as arguments to
format_typemap_generator_args.py. If they change, build/gyp_chromium needs to be
rerun to pick up the changes.

+      ],
+      'outputs': [ '<(output)' ],
+    },
   ],
   'rules': [
     {
@@ -78,8 +88,8 @@
       },
       'inputs': [
         '<@(mojom_bindings_generator_sources)',
-        '<@(mojom_typemaps)',
         '<(stamp_filename)',
+        '<(mojom_typemap_file)',
         '<(SHARED_INTERMEDIATE_DIR)/mojo/public/tools/bindings/cpp_templates.zip',
         '<(SHARED_INTERMEDIATE_DIR)/mojo/public/tools/bindings/java_templates.zip',
         '<(SHARED_INTERMEDIATE_DIR)/mojo/public/tools/bindings/js_templates.zip',
@@ -110,8 +120,8 @@
         '--java_output_directory=<(java_out_dir)',
         '--variant', '<(mojom_variant)',
         '-g', '<(mojom_output_languages)',
-        '<@(mojom_generator_typemap_args)',
-        '<@(mojom_extra_generator_args)',
+        '--typemap',
+        '<(mojom_typemap_file)',
         '<@(mojom_generator_wtf_arg)',
         '--bytecode_path',
         '<(SHARED_INTERMEDIATE_DIR)/mojo/public/tools/bindings',
@@ -124,11 +134,9 @@
     '<(DEPTH)/base/base.gyp:base',
     '<(DEPTH)/mojo/mojo_public.gyp:mojo_interface_bindings_generation',
     '<(DEPTH)/mojo/public/tools/bindings/bindings.gyp:precompile_mojom_bindings_generator_templates',
-    '<@(mojom_typemap_dependencies)',
     '<@(wtf_dependencies)',
   ],
   'export_dependent_settings': [
-    '<@(mojom_typemap_dependencies)',
     '<@(wtf_dependencies)',
   ],
   'include_dirs': [