[mojo] Add typemap and variant support to generators

mojo/public/tools/bindings/generators/mojom_js_generator.py

 # 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.
 
 """Generates JavaScript source files from a mojom.Module."""
 
 import mojom.generate.generator as generator
 import mojom.generate.module as mojom
 import mojom.generate.pack as pack
 from mojom.generate.template_expander import UseJinja
@@ skipping 367 matching lines @@
       "unions": self.GetUnions(),
       "interfaces": self.GetInterfaces(),
       "imported_interfaces": self.GetImportedInterfaces(),
     }
 
   @UseJinja("js_templates/module.amd.tmpl", filters=js_filters)
   def GenerateAMDModule(self):
     return self.GetParameters()
 
   def GenerateFiles(self, args):
+    if self.variant:
+      raise Exception("Variants not supported in JavaScript bindings.")
+
     self.Write(self.GenerateAMDModule(),
         self.MatchMojomFilePath("%s.js" % self.module.name))
 
   def GetImports(self):
     used_names = set()
     for each_import in self.module.imports:
       simple_name = each_import["module_name"].split(".")[0]
 
       # Since each import is assigned a variable in JS, they need to have unique
       # names.
       unique_name = simple_name
       counter = 0
       while unique_name in used_names:
         counter += 1
         unique_name = simple_name + str(counter)
 
       used_names.add(unique_name)
       each_import["unique_name"] = unique_name + "$"
       counter += 1
     return self.module.imports
 
   def GetImportedInterfaces(self):
     interface_to_import = {};
     for each_import in self.module.imports:
       for each_interface in each_import["module"].interfaces:
         name = each_interface.name
         interface_to_import[name] = each_import["unique_name"] + "." + name
     return interface_to_import;