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 77684bf7909cb48762f8747f38a8a73c2323d3c7..44a74ed5fea97282ce307cafd3d88df161da1adc 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -2479,6 +2479,12 @@ 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.
    */