mojom: Add associative arrays to the mojom language.

mojo/public/tools/bindings/pylib/mojom/parse/translate.py

Index: mojo/public/tools/bindings/pylib/mojom/parse/translate.py
diff --git a/mojo/public/tools/bindings/pylib/mojom/parse/translate.py b/mojo/public/tools/bindings/pylib/mojom/parse/translate.py
index 77e92c5b8b2065c59ebb7453aa18b7b298cce3f9..f2538b6deffaf71403f700a224c584823c609e23 100644
--- a/mojo/public/tools/bindings/pylib/mojom/parse/translate.py
+++ b/mojo/public/tools/bindings/pylib/mojom/parse/translate.py
@@ -56,6 +56,10 @@ def _MapKind(kind):
     if typename.find('[') != -1:
       raise Exception('Fixed sized arrays of arrays not supported')
     return 'a' + kind[lbracket+1:-1] + ':' + _MapKind(typename)
+  if kind.endswith('}'):
+    lbracket = kind.rfind('{')
+    value = kind[0:lbracket]
+    return 'm[' + _MapKind(kind[lbracket+1:-1]) + '][' + _MapKind(value) + ']'
   if kind.endswith('&'):
     return 'r:' + _MapKind(kind[0:-1])
   if kind in map_to_kind: