Properly initialize element-transitioning array literals on ARM.

src/arm/macro-assembler-arm.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 785 matching lines @@
                                Label* fail);
 
   // Check if a map for a JSObject indicates that the object has fast smi only
   // elements.  Jump to the specified label if it does not.
   void CheckFastSmiOnlyElements(Register map,
                                 Register scratch,
                                 Label* fail);
 
   // Check to see if maybe_number can be stored as a double in
   // FastDoubleElements. If it can, store it at the index specified by key in
-  // the FastDoubleElements array elements, otherwise jump to fail.
+  // the FastDoubleElements array elements. Otherwise jump to fail, in which
+  // case scratch2, scratch3 and scratch4 are unmodified.
   void StoreNumberToDoubleElements(Register value_reg,
                                    Register key_reg,
                                    Register receiver_reg,
                                    Register elements_reg,
                                    Register scratch1,
                                    Register scratch2,
                                    Register scratch3,
                                    Register scratch4,
                                    Label* fail);
 
@@ skipping 553 matching lines @@
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_MACRO_ASSEMBLER_ARM_H_