A64: Remove two TODOs that will not be done.

src/a64/builtins-a64.cc

 // Copyright 2013 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 666 matching lines @@
     // Push the function and the receiver onto the stack.
     __ Push(function, receiver);
 
     // Copy arguments to the stack in a loop, in reverse order.
     // x3: argc.
     // x4: argv.
     Label loop, entry;
     // Compute the copy end address.
     __ Add(x10, argv, Operand(argc, LSL, kPointerSizeLog2));
 
-    // TODO(all): This can potentially be optimized with ldp/stp to speed up
-    // arguments passing from C++ to JS.
     __ B(&entry);
     __ Bind(&loop);
     __ Ldr(x11, MemOperand(argv, kPointerSize, PostIndex));
     __ Ldr(x12, MemOperand(x11));  // Dereference the handle.
     __ Push(x12);  // Push the argument.
     __ Bind(&entry);
     __ Cmp(x10, argv);
     __ B(ne, &loop);
 
     // Initialize all JavaScript callee-saved registers, since they will be seen
@@ skipping 775 matching lines @@
   __ Bind(&dont_adapt_arguments);
   __ Jump(x3);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM