Bug 913923 - Part a: Move UnionMember into its own header; r=dzbarsky

dom/bindings/BindingUtils.h

@@ -1612,37 +1612,6 @@ ConvertJSValueToByteString(JSContext* cx, JS::Handle<JS::Value> v,
                            JS::MutableHandle<JS::Value> pval, bool nullable,
                            nsACString& result);
 
-// Class for holding the type of members of a union. The union type has an enum
-// to keep track of which of its UnionMembers has been constructed.
-template<class T>
-class UnionMember {
-    AlignedStorage2<T> storage;
-
-public:
-    T& SetValue() {
-      new (storage.addr()) T();
-      return *storage.addr();
-    }
-    template <typename T1>
-    T& SetValue(const T1 &t1)
-    {
-      new (storage.addr()) T(t1);
-      return *storage.addr();
-    }
-    template <typename T1, typename T2>
-    T& SetValue(const T1 &t1, const T2 &t2)
-    {
-      new (storage.addr()) T(t1, t2);
-      return *storage.addr();
-    }
-    const T& Value() const {
-      return *storage.addr();
-    }
-    void Destroy() {
-      storage.addr()->~T();
-    }
-};
-
 template<typename T>
 void DoTraceSequence(JSTracer* trc, FallibleTArray<T>& seq);
 template<typename T>

dom/bindings/Codegen.py

@@ -10522,6 +10522,7 @@ struct PrototypeTraits;
                                             config.getCallbacks(),
                                             config)
         includes.add("mozilla/dom/BindingUtils.h")
+        includes.add("mozilla/dom/UnionMember.h")
 
         # Wrap all of that in our namespaces.
         curr = CGNamespace.build(['mozilla', 'dom'], unions)

dom/bindings/UnionMember.h

@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* A class for holding the members of a union. */
+
+#ifndef mozilla_dom_UnionMember_h
+#define mozilla_dom_UnionMember_h
+
+#include "mozilla/Alignment.h"
+
+namespace mozilla {
+namespace dom {
+
+// The union type has an enum to keep track of which of its UnionMembers has
+// been constructed.
+template<class T>
+class UnionMember
+{
+  AlignedStorage2<T> mStorage;
+
+public:
+  T& SetValue()
+  {
+    new (mStorage.addr()) T();
+    return *mStorage.addr();
+  }
+  template <typename T1>
+  T& SetValue(const T1& aValue)
+  {
+    new (mStorage.addr()) T(aValue);
+    return *mStorage.addr();
+  }
+  template<typename T1, typename T2>
+  T& SetValue(const T1& aValue1, const T2& aValue2)
+  {
+    new (mStorage.addr()) T(aValue1, aValue2);
+    return *mStorage.addr();
+  }
+  const T& Value() const
+  {
+    return *mStorage.addr();
+  }
+  void Destroy()
+  {
+    mStorage.addr()->~T();
+  }
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_UnionMember_h

dom/bindings/moz.build

@@ -27,6 +27,7 @@ EXPORTS.mozilla.dom += [
     'Nullable.h',
     'PrimitiveConversions.h',
     'TypedArray.h',
+    'UnionMember.h',
 ]
 
 FAIL_ON_WARNINGS = True