Return Object* instead of MaybeObject* from runtime calls.

src/runtime.h

 // Copyright 2012 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 872 matching lines @@
     ARRAY_ID_FLOAT64 = 8,
     ARRAY_ID_UINT8_CLAMPED = 9
   };
 
   static void ArrayIdToTypeAndSize(int array_id,
       ExternalArrayType *type,
       ElementsKind* external_elements_kind,
       ElementsKind* fixed_elements_kind,
       size_t *element_size);
 
-  // Helper functions used stubs.
-  static void PerformGC(Object* result, Isolate* isolate);
-  static void OutOfMemory();
-
   // Used in runtime.cc and hydrogen's VisitArrayLiteral.
   MUST_USE_RESULT static MaybeHandle<Object> CreateArrayLiteralBoilerplate(
       Isolate* isolate,
       Handle<FixedArray> literals,
       Handle<FixedArray> elements);
 };
 
 
 //---------------------------------------------------------------------------
 // Constants used by interface to runtime functions.
 
 class AllocateDoubleAlignFlag:  public BitField<bool,            0, 1> {};
 class AllocateTargetSpace:      public BitField<AllocationSpace, 1, 3> {};
 
 class DeclareGlobalsEvalFlag:   public BitField<bool,       0, 1> {};
 class DeclareGlobalsNativeFlag: public BitField<bool,       1, 1> {};
 class DeclareGlobalsStrictMode: public BitField<StrictMode, 2, 1> {};
 
 } }  // namespace v8::internal
 
 #endif  // V8_RUNTIME_H_