IDL: Put generated union type containers in separate files

Source/bindings/tests/results/core/DoubleOrString.h

+// Copyright 2015 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.
+
+// This file has been auto-generated by code_generator_v8.py. DO NOT MODIFY!
+
+#ifndef DoubleOrString_h
+#define DoubleOrString_h
+
+#include "bindings/core/v8/Dictionary.h"
+#include "bindings/core/v8/ExceptionState.h"
+#include "bindings/core/v8/V8Binding.h"
+#include "platform/heap/Handle.h"
+
+namespace blink {
+
+class DoubleOrString final {
+    ALLOW_ONLY_INLINE_ALLOCATION();
+public:
+    DoubleOrString();
+    bool isNull() const { return m_type == SpecificTypeNone; }
+
+    bool isDouble() const { return m_type == SpecificTypeDouble; }
+    double getAsDouble() const;
+    void setDouble(double);
+    static DoubleOrString fromDouble(double);
+
+    bool isString() const { return m_type == SpecificTypeString; }
+    String getAsString() const;
+    void setString(String);
+    static DoubleOrString fromString(String);
+
+private:
+    enum SpecificTypes {
+        SpecificTypeNone,
+        SpecificTypeDouble,
+        SpecificTypeString,
+    };
+    SpecificTypes m_type;
+
+    double m_double;
+    String m_string;
+
+    friend v8::Local<v8::Value> toV8(const DoubleOrString&, v8::Local<v8::Object>, v8::Isolate*);
+};
+
+class V8DoubleOrString final {
+public:
+    static void toImpl(v8::Isolate*, v8::Local<v8::Value>, DoubleOrString&, ExceptionState&);
+};
+
+v8::Local<v8::Value> toV8(const DoubleOrString&, v8::Local<v8::Object>, v8::Isolate*);
+
+template <class CallbackInfo>
+inline void v8SetReturnValue(const CallbackInfo& callbackInfo, DoubleOrString& impl)
+{
+    v8SetReturnValue(callbackInfo, toV8(impl, callbackInfo.Holder(), callbackInfo.GetIsolate()));
+}
+
+template <>
+struct NativeValueTraits<DoubleOrString> {
+    static DoubleOrString nativeValue(const v8::Local<v8::Value>&, v8::Isolate*, ExceptionState&);
+};
+
+class V8DoubleOrStringOrNull final {
+public:
+    static void toImpl(v8::Isolate* isolate, v8::Local<v8::Value> v8Value, DoubleOrString& impl, ExceptionState& exceptionState)
+    {
+        if (isUndefinedOrNull(v8Value))
+            return;
+        V8DoubleOrString::toImpl(isolate, v8Value, impl, exceptionState);
+    }
+};
+
+} // namespace blink
+
+#endif // DoubleOrString_h