Remove unused typemap includes from generated C++ mojo bindings.

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

Index: mojo/public/tools/bindings/generators/mojom_cpp_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_cpp_generator.py b/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
index e66bec38bd32749d604981de050d1c91755535ec..c75013badf88a19cab5a678a1b77174e20c877fc 100644
--- a/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_cpp_generator.py
@@ -191,10 +191,8 @@ def IsHashableKind(kind):
         return False
       return all(Check(field.kind) for field in kind.fields)
     elif mojom.IsEnumKind(kind):
-      if (IsTypemappedKind(kind) and
-          not _current_typemap[GetFullMojomNameForKind(kind)]["hashable"]):
-        return False
-      return True
+      return not IsTypemappedKind(kind) or _current_typemap[
+          GetFullMojomNameForKind(kind)]["hashable"]
     elif mojom.IsUnionKind(kind):
       return all(Check(field.kind) for field in kind.fields)
     elif mojom.IsAnyHandleKind(kind):
@@ -419,8 +417,7 @@ def GetUnmappedTypeForSerializer(kind):
 
 def TranslateConstants(token, kind):
   if isinstance(token, mojom.NamedValue):
-    return _NameFormatter(token, _variant).FormatForCpp(
-        flatten_nested_kind=True)
+    return GetNameForKind(token, flatten_nested_kind=True)
 
   if isinstance(token, mojom.BuiltinValue):
     if token.value == "double.INFINITY":
@@ -575,7 +572,6 @@ class Generator(generator.Generator):
     "is_typemapped_kind": IsTypemappedKind,
     "is_union_kind": mojom.IsUnionKind,
     "passes_associated_kinds": mojom.PassesAssociatedKinds,
-    "struct_size": lambda ps: ps.GetTotalSize() + _HEADER_SIZE,
     "stylize_method": generator.StudlyCapsToCamel,
     "under_to_camel": generator.UnderToCamel,
     "unmapped_type_for_serializer": GetUnmappedTypeForSerializer,
@@ -583,15 +579,81 @@ class Generator(generator.Generator):
 
   def GetExtraTraitsHeaders(self):
     extra_headers = set()
-    for entry in self.typemap.itervalues():
-      extra_headers.update(entry.get("traits_headers", []))
-    return list(extra_headers)
+    for typemap in self._GetAllUsedTypemaps():
+      extra_headers.update(typemap.get("traits_headers", []))
+    return sorted(extra_headers)
+
+  def _GetAllUsedTypemaps(self):
+    """Returns the typemaps for types needed for serialization in this module.
+
+    A type is needed for serialization if it is contained by a struct or union
+    defined in this module, is a parameter of a message in an interface in
+    this module or is contained within another type needed for serialization.
+    """
+    used_typemaps = []
+    seen_types = set()
+    def AddKind(kind):
+      if (mojom.IsIntegralKind(kind) or mojom.IsStringKind(kind) or
+          mojom.IsDoubleKind(kind) or mojom.IsFloatKind(kind) or
+          mojom.IsAnyHandleKind(kind) or
+          mojom.IsInterfaceKind(kind) or
+          mojom.IsInterfaceRequestKind(kind) or
+          mojom.IsAssociatedKind(kind)):
+        pass
+      elif mojom.IsArrayKind(kind):
+        AddKind(kind.kind)
+      elif mojom.IsMapKind(kind):
+        AddKind(kind.key_kind)
+        AddKind(kind.value_kind)
+      else:
+        name = GetFullMojomNameForKind(kind)
+        if name in seen_types:
+          return
+        seen_types.add(name)
+
+        typemap = _current_typemap.get(name, None)
+        if typemap:
+          used_typemaps.append(typemap)
+        if mojom.IsStructKind(kind) or mojom.IsUnionKind(kind):
+          for field in kind.fields:
+            AddKind(field.kind)
+
+    for kind in self.module.structs + self.module.unions:
+      for field in kind.fields:
+        AddKind(field.kind)
+
+    for interface in self.module.interfaces:
+      for method in interface.methods:
+        for parameter in method.parameters + (method.response_parameters or []):
+          AddKind(parameter.kind)
+
+    return used_typemaps
 
   def GetExtraPublicHeaders(self):
-    extra_headers = set()
-    for entry in self.typemap.itervalues():
-      extra_headers.update(entry.get("public_headers", []))
-    return list(extra_headers)
+    all_enums = list(self.module.enums)
+    for struct in self.module.structs:
+      all_enums.extend(struct.enums)
+    for interface in self.module.interfaces:
+      all_enums.extend(interface.enums)
+
+    types = set(GetFullMojomNameForKind(typename)
+                for typename in
+                self.module.structs + all_enums + self.module.unions)
+    headers = set()
+    for typename, typemap in self.typemap.iteritems():
+      if typename in types:
+        headers.update(typemap.get("public_headers", []))
+    return sorted(headers)
+
+  def _GetDirectlyUsedKinds(self):
+    for struct in self.module.structs + self.module.unions:
+      for field in struct.fields:
+        yield field.kind
+
+    for interface in self.module.interfaces:
+      for method in interface.methods:
+        for param in method.parameters + (method.response_parameters or []):
+          yield param.kind
 
   def GetJinjaExports(self):
     structs = self.GetStructs()