mojo: Generate top level enums for python bindings.

mojo/public/tools/bindings/pylib/mojom/generate/data.py

Index: mojo/public/tools/bindings/pylib/mojom/generate/data.py
diff --git a/mojo/public/tools/bindings/pylib/mojom/generate/data.py b/mojo/public/tools/bindings/pylib/mojom/generate/data.py
index 52e2f7d7386d6844a5de08185e45d049dcdf803a..130eba45c42a953b5a38209fa9d2371711d309ae 100644
--- a/mojo/public/tools/bindings/pylib/mojom/generate/data.py
+++ b/mojo/public/tools/bindings/pylib/mojom/generate/data.py
@@ -102,6 +102,8 @@ def FixupExpression(module, value, scope, kind):
     # Allow user defined values to shadow builtins.
     result = LookupValue(module.values, value[1], scope, kind)
     if result:
+      if isinstance(result, tuple):
+        raise Exception('Unable to resolve expression: %r' % value[1])

[viettrungluu, 2014/09/05 17:05:30]

Does this properly handle, e.g., using constants as default values to fields?

[qsr, 2014/09/08 09:06:08]

 Yes, we do have this in our test cases
(mojo/public/interfaces/bindings/tests/sample_service.mojom). What it prevents
us to do is used a constant as a value for an enum. If we want to support this,
we will need to have LookupValue returns the right NamedValue here instead of
letting the  tuple untouched.

       return result
     if IsBuiltinValue(value[1]):
       return mojom.BuiltinValue(value[1])