Revert r20974: Unify and simplify the FastCloneShallowArrayStub

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index df5e68fe82e319c8020f84164a0fbc737dcf45f2..ecf58c977813ac81d6e85cac5c1133b2e26c8c35 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -82,11 +82,6 @@ void FastCloneShallowArrayStub::InitializeInterfaceDescriptor(
   static Register registers[] = { rax, rbx, rcx };
   descriptor->register_param_count_ = 3;
   descriptor->register_params_ = registers;
-  static Representation representations[] = {
-    Representation::Tagged(),
-    Representation::Smi(),
-    Representation::Tagged() };
-  descriptor->register_param_representations_ = representations;
   descriptor->deoptimization_handler_ =
       Runtime::FunctionForId(
           Runtime::kHiddenCreateArrayLiteralStubBailout)->entry;
@@ -216,11 +211,6 @@ static void InitializeArrayConstructorDescriptor(
     descriptor->handler_arguments_mode_ = PASS_ARGUMENTS;
     descriptor->stack_parameter_count_ = rax;
     descriptor->register_param_count_ = 3;
-    static Representation representations[] = {
-        Representation::Tagged(),
-        Representation::Tagged(),
-        Representation::Integer32() };
-    descriptor->register_param_representations_ = representations;
     descriptor->register_params_ = registers_variable_args;
   }
 
@@ -249,10 +239,6 @@ static void InitializeInternalArrayConstructorDescriptor(
     descriptor->stack_parameter_count_ = rax;
     descriptor->register_param_count_ = 2;
     descriptor->register_params_ = registers_variable_args;
-    static Representation representations[] = {
-        Representation::Tagged(),
-        Representation::Integer32() };
-    descriptor->register_param_representations_ = representations;
   }
 
   descriptor->hint_stack_parameter_count_ = constant_stack_parameter_count;