Flush out potential leaks of Failure objects

src/heap.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 1909 matching lines @@
   bool CreateInitialMaps();
   bool CreateInitialObjects();
 
   // These five Create*EntryStub functions are here and forced to not be inlined
   // because of a gcc-4.4 bug that assigns wrong vtable entries.
   NO_INLINE(void CreateJSEntryStub());
   NO_INLINE(void CreateJSConstructEntryStub());
 
   void CreateFixedStubs();
 
-  MaybeObject* CreateOddball(const char* to_string,
-                             Object* to_number,
-                             byte kind);
+  MUST_USE_RESULT MaybeObject* CreateOddball(const char* to_string,
+                                             Object* to_number,
+                                             byte kind);
 
   // Allocate a JSArray with no elements
   MUST_USE_RESULT MaybeObject* AllocateJSArray(
       ElementsKind elements_kind,
       PretenureFlag pretenure = NOT_TENURED);
 
   // Allocate empty fixed array.
   MUST_USE_RESULT MaybeObject* AllocateEmptyFixedArray();
 
   // Allocate empty fixed double array.
@@ skipping 894 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_