[turbofan] add RegisterConfiguration to decouple arch specific register layouts from compiler

test/unittests/compiler/instruction-selector-unittest.cc

Index: test/unittests/compiler/instruction-selector-unittest.cc
diff --git a/test/unittests/compiler/instruction-selector-unittest.cc b/test/unittests/compiler/instruction-selector-unittest.cc
index 57ce6908327f5c71d76f2a45fa2d381788ece7af..c79a9e4eaa0380208c15818b2d289618081b8d0d 100644
--- a/test/unittests/compiler/instruction-selector-unittest.cc
+++ b/test/unittests/compiler/instruction-selector-unittest.cc
@@ -46,8 +46,10 @@ InstructionSelectorTest::Stream InstructionSelectorTest::StreamBuilder::Build(
   selector.SelectInstructions();
   if (FLAG_trace_turbo) {
     OFStream out(stdout);
+    PrintableInstructionSequence printable = {
+        RegisterConfiguration::ArchDefault(), &sequence};
     out << "=== Code sequence after instruction selection ===" << std::endl
-        << sequence;
+        << printable;
   }
   Stream s;
   // Map virtual registers.