Add CallAsFunction method to the Object class in the API

src/execution.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 120 matching lines @@
   static void ProcessDebugMesssages(bool debug_command_only);
 #endif
 
   // If the stack guard is triggered, but it is not an actual
   // stack overflow, then handle the interruption accordingly.
   MUST_USE_RESULT static MaybeObject* HandleStackGuardInterrupt();
 
   // Get a function delegate (or undefined) for the given non-function
   // object. Used for support calling objects as functions.
   static Handle<Object> GetFunctionDelegate(Handle<Object> object);
+  static Handle<Object> TryGetFunctionDelegate(Handle<Object> object,
+                                               bool* has_pending_exception);
 
   // Get a function delegate (or undefined) for the given non-function
   // object. Used for support calling objects as constructors.
   static Handle<Object> GetConstructorDelegate(Handle<Object> object);
 };
 
 
 class ExecutionAccess;
 class Isolate;
 
@@ skipping 131 matching lines @@
   friend class StackLimitCheck;
   friend class PostponeInterruptsScope;
 
   DISALLOW_COPY_AND_ASSIGN(StackGuard);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_EXECUTION_H_