Make classes for union types exported.

Source/bindings/templates/union.h

 // Copyright 2014 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}}. DO NOT MODIFY!
 
 #ifndef {{macro_guard}}
 #define {{macro_guard}}
 
 {% for filename in header_includes %}
 #include "{{filename}}"
 {% endfor %}
 
 namespace blink {
 
 {% for decl in header_forward_decls %}
 class {{decl}};
 {% endfor %}
 
 {% for container in containers %}
-class {{container.cpp_class}} final {
+class {{exported}}{{container.cpp_class}} final {
     ALLOW_ONLY_INLINE_ALLOCATION();
 public:
     {{container.cpp_class}}();
     bool isNull() const { return m_type == SpecificTypeNone; }
 
     {% for member in container.members %}
     bool is{{member.type_name}}() const { return m_type == {{member.specific_type_enum}}; }
     {{member.rvalue_cpp_type}} getAs{{member.type_name}}() const;
     void set{{member.type_name}}({{member.rvalue_cpp_type}});
     static {{container.cpp_class}} from{{member.type_name}}({{member.rvalue_cpp_type}});
 
     {% endfor %}
+#if COMPILER(MSVC) && defined(COMPONENT_BUILD) && LINK_CORE_MODULES_SEPARATELY

[haraken, 2015/04/02 09:13:09]

It would be better to change LINK_CORE_MODULES_SEPARATELY to a gyp flag and
remove defined(COMPONENT_BUILD) from here. A follow-up CL is fine.

+    // Explicit declarations of copy constructor, destructor and operator=,
+    // because msvc automatically generates them if they are not declared in
+    // this header.
+    {{container.cpp_class}}(const {{container.cpp_class}}&);
+    ~{{container.cpp_class}}();
+    {{container.cpp_class}}& operator=(const {{container.cpp_class}}&);
+#endif
     {% if container.needs_trace %}
     DECLARE_TRACE();
 
     {% endif %}
 private:
     enum SpecificTypes {
         SpecificTypeNone,
         {% for member in container.members %}
         {{member.specific_type_enum}},
         {% endfor %}
     };
     SpecificTypes m_type;
 
     {% for member in container.members %}
     {{member.cpp_type}} m_{{member.cpp_name}};
     {% endfor %}
 
-    friend v8::Local<v8::Value> toV8(const {{container.cpp_class}}&, v8::Local<v8::Object>, v8::Isolate*);
+    friend {{exported}}v8::Local<v8::Value> toV8(const {{container.cpp_class}}&, v8::Local<v8::Object>, v8::Isolate*);
 };
 
 class V8{{container.cpp_class}} final {
 public:
-    static void toImpl(v8::Isolate*, v8::Local<v8::Value>, {{container.cpp_class}}&, ExceptionState&);
+    {{exported}}static void toImpl(v8::Isolate*, v8::Local<v8::Value>, {{container.cpp_class}}&, ExceptionState&);
 };
 
-v8::Local<v8::Value> toV8(const {{container.cpp_class}}&, v8::Local<v8::Object>, v8::Isolate*);
+{{exported}}v8::Local<v8::Value> toV8(const {{container.cpp_class}}&, v8::Local<v8::Object>, v8::Isolate*);
 
 template <class CallbackInfo>
 inline void v8SetReturnValue(const CallbackInfo& callbackInfo, {{container.cpp_class}}& impl)
 {
     v8SetReturnValue(callbackInfo, toV8(impl, callbackInfo.Holder(), callbackInfo.GetIsolate()));
 }
 
 template <>
 struct NativeValueTraits<{{container.cpp_class}}> {
     static {{container.cpp_class}} nativeValue(v8::Isolate*, v8::Local<v8::Value>, ExceptionState&);
@@ skipping 10 matching lines @@
         if (isUndefinedOrNull(v8Value))
             return;
         V8{{cpp_type}}::toImpl(isolate, v8Value, impl, exceptionState);
     }
 };
 
 {% endfor %}
 } // namespace blink
 
 #endif // {{macro_guard}}