Fix up how the JSON Schema compiler decides whether to include or forward

tools/json_schema_compiler/schema_util.py

Index: tools/json_schema_compiler/schema_util.py
diff --git a/tools/json_schema_compiler/schema_util.py b/tools/json_schema_compiler/schema_util.py
index e71be8ba33a9d3cea09f051087f172fced585527..7ce399e8ed31e0a0a75a76d82176a39a9a00e6a1 100644
--- a/tools/json_schema_compiler/schema_util.py
+++ b/tools/json_schema_compiler/schema_util.py
@@ -9,15 +9,19 @@ import json_parse
 def CapitalizeFirstLetter(value):
   return value[0].capitalize() + value[1:]
 
-def GetNamespace(ref_type):
-  if '.' in ref_type:
-    return ref_type[:ref_type.rindex('.')]
+def GetNamespace(ref):
+  return SplitNamespace(ref)[0]
 
-def StripSchemaNamespace(s):
-  last_dot = s.rfind('.')
-  if not last_dot == -1:
-    return s[last_dot + 1:]
-  return s
+def StripNamespace(ref):
+  return SplitNamespace(ref)[1]
+
+def SplitNamespace(ref):
+  """Returns (namespace, entity) from |ref|, e.g. app.window.AppWindow ->
+  (app.window, AppWindow). If |ref| isn't qualified then returns (None, ref).
+  """
+  if '.' in ref:
+    return tuple(ref.rsplit('.', 1))
+  return (None, ref)
 
 def JsFunctionNameToClassName(namespace_name, function_name):
   """Transform a fully qualified function name like foo.bar.baz into FooBarBaz