Only generate code for files that are specified, not their imports.

mojo/public/tools/bindings/run_code_generators.py

Index: mojo/public/tools/bindings/run_code_generators.py
diff --git a/mojo/public/tools/bindings/run_code_generators.py b/mojo/public/tools/bindings/run_code_generators.py
index a6d30946a1dd44a94729a9157dad5945e5e9a622..07227ef8f3e79a75a6c457fa8c9d3e5cf5be1718 100755
--- a/mojo/public/tools/bindings/run_code_generators.py
+++ b/mojo/public/tools/bindings/run_code_generators.py
@@ -22,6 +22,9 @@ def _ParseCLIArgs():
   """
   parser = argparse.ArgumentParser(
       description='Generate bindings from mojom parser output.')
+  parser.add_argument('filenames', nargs='*',
+                      help='Mojom files to be generated. If empty, every file'

[rudominer, 2016/01/07 22:25:49]

"Mojom files to be generated" is not a precise description for a couple of
reasons:
(1) We are not generating mojom files.
(2) This is only a filter over the set of file names in the file graph, i.e. if
you add a file name here that is not in the file graph it will not cause a file
to be generated.

I suggest: "Filter on the set of .mojom files for which code will be generated.
If empty, code will be generated for every file in the provided graph."

+                      'in the provided graph will be generated.')
   parser.add_argument('-f', '--file-graph', dest='file_graph',
                       help='Location of the parser output. "-" for stdin. '
                       '(default "-")', default='-')
@@ -152,8 +155,16 @@ def main():
   modules = mojom_translator.TranslateFileGraph(mojom_file_graph)
 
   generator_modules = LoadGenerators(args.generators_string)
+  filenames = set(os.path.basename(filename) for filename in args.filenames)
 
   for _, module in modules.iteritems():
+    # If filenames are specified on the command line, only generate code for
+    # the specified mojom files.
+    # TODO(azani): This is not as robust as we would like since files with the
+    # same name but different paths or files resolved through links might not
+    # be correctly identified by module.name.
+    if filenames and module.name not in filenames:
+      continue
     FixModulePath(module, os.path.abspath(args.depth))
     for generator_module in generator_modules:
       generator = generator_module.Generator(module, args.output_dir)