Clean up some uses of Failures and MaybeObjects.

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index 698c81fe833f07250ff2749582560ddccee5e625..37a9636c39587daba2ceb7a083ad0321c0a6c813 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -1012,13 +1012,6 @@ class MacroAssembler: public Assembler {
                                  Register scratch,
                                  AllocationFlags flags);
 
-  // Helper for PopHandleScope.  Allowed to perform a GC and returns
-  // NULL if gc_allowed.  Does not perform a GC if !gc_allowed, and
-  // possibly returns a failure object indicating an allocation failure.
-  MUST_USE_RESULT MaybeObject* PopHandleScopeHelper(Register saved,
-                                                    Register scratch,
-                                                    bool gc_allowed);
-
   // Helper for implementing JumpIfNotInNewSpace and JumpIfInNewSpace.
   void InNewSpace(Register object,
                   Register scratch,