Introduce collective --harmony flag.

src/x64/full-codegen-x64.cc

 // Copyright 2011 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 2011 matching lines @@
     __ push(Operand(rsp, arg_count * kPointerSize));
   } else {
     __ PushRoot(Heap::kUndefinedValueRootIndex);
   }
 
   // Push the receiver of the enclosing function and do runtime call.
   __ push(Operand(rbp, (2 + info_->scope()->num_parameters()) * kPointerSize));
 
   // Push the strict mode flag. In harmony mode every eval call
   // is a strict mode eval call.
-  StrictModeFlag strict_mode = strict_mode_flag();
-  if (FLAG_harmony_block_scoping) {
-    strict_mode = kStrictMode;
-  }
+  StrictModeFlag strict_mode =
+      FLAG_harmony_scoping ? kStrictMode : strict_mode_flag();
   __ Push(Smi::FromInt(strict_mode));
 
   __ CallRuntime(flag == SKIP_CONTEXT_LOOKUP
                  ? Runtime::kResolvePossiblyDirectEvalNoLookup
                  : Runtime::kResolvePossiblyDirectEval, 4);
 }
 
 
 void FullCodeGenerator::VisitCall(Call* expr) {
 #ifdef DEBUG
@@ skipping 2151 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64