Remove passing of argc in r0 when calling builtins on ARM as it is not used

src/arm/virtual-frame-arm.cc

 // Copyright 2009 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 225 matching lines @@
 
 void VirtualFrame::CallRuntime(Runtime::FunctionId id, int arg_count) {
   PrepareForCall(arg_count, arg_count);
   ASSERT(cgen()->HasValidEntryRegisters());
   __ CallRuntime(id, arg_count);
 }
 
 
 void VirtualFrame::InvokeBuiltin(Builtins::JavaScript id,
                                  InvokeJSFlags flags,
-                                 Result* arg_count_register,
                                  int arg_count) {
-  ASSERT(arg_count_register->reg().is(r0));
   PrepareForCall(arg_count, arg_count);
-  arg_count_register->Unuse();
   __ InvokeBuiltin(id, flags);
 }
 
 
 void VirtualFrame::RawCallCodeObject(Handle<Code> code,
                                      RelocInfo::Mode rmode) {
   ASSERT(cgen()->HasValidEntryRegisters());
   __ Call(code, rmode);
 }
 
@@ skipping 125 matching lines @@
   ASSERT(stack_pointer_ == element_count() - 1);
   elements_.Add(FrameElement::MemoryElement());
   stack_pointer_++;
   __ push(reg);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal