IDL: Use Nullable for union type return value

Source/bindings/core/v8/Nullable.h

Index: Source/bindings/core/v8/Nullable.h
diff --git a/Source/bindings/core/v8/Nullable.h b/Source/bindings/core/v8/Nullable.h
index 6d3cb441a790f2c515ad27c55221c621e7d0c893..f019f7f53a9874a7fd856209a4837308ff41b54c 100644
--- a/Source/bindings/core/v8/Nullable.h
+++ b/Source/bindings/core/v8/Nullable.h
@@ -33,7 +33,13 @@ public:
         return *this;
     }
 
+    void set(const T& value)
+    {
+        m_value = value;
+        m_isNull = false;
+    }
     const T& get() const { ASSERT(!m_isNull); return m_value; }
+    T& get() { ASSERT(!m_isNull); return m_value; }
     bool isNull() const { return m_isNull; }
 
     operator bool() const { return !m_isNull && m_value; }

[haraken, 2014/08/13 13:07:10]

In order to allow implicit conversion to bool but prevent implicit conversion to
other integer types, can we use the "UnspecifiedBoolType trick" in RefPtr.h?

[bashi, 2014/08/13 13:45:56]

Will do.

[bashi, 2014/08/15 02:43:53]

It turns out we need a meta-function or need to rely on SFINAE to make this
workable for *Ptr family. Since there is no call site at this point, I'd rather
remove this. We can re-add it when we need it.