Expose v8::Function::GetDisplayName to public API.

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 1ec04816871f8000ba7032654b71ae7bcb9f0802..b6461b55d89027f4692564df7cb9568326d3451c 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -2478,6 +2478,12 @@ class V8_EXPORT Function : public Object {
   Handle<Value> GetInferredName() const;
 
   /**
+   * User-defined name assigned to the "displayName" property of this function.
+   * Used to facilitate debugging and profiling of JavaScript code.
+   */
+  Handle<Value> GetDisplayName() const;
+
+  /**
    * Returns zero based line number of function body and
    * kLineOffsetNotFound if no information available.
    */