Stop converting from Location to ManagedRegister.

Now the source of truth is the Location object that knows
which register (core, pair, fpu) it needs to refer to.

Change-Id: I62401343d7479ecfb24b5ed161ec7829cda5a0b1
diff --git a/compiler/optimizing/graph_visualizer.cc b/compiler/optimizing/graph_visualizer.cc
index 686a0b0..b4eb89d 100644
--- a/compiler/optimizing/graph_visualizer.cc
+++ b/compiler/optimizing/graph_visualizer.cc
@@ -123,9 +123,9 @@
   void DumpLocation(Location location, Primitive::Type type) {
     if (location.IsRegister()) {
       if (type == Primitive::kPrimDouble || type == Primitive::kPrimFloat) {
-        codegen_.DumpFloatingPointRegister(output_, location.reg().RegId());
+        codegen_.DumpFloatingPointRegister(output_, location.reg());
       } else {
-        codegen_.DumpCoreRegister(output_, location.reg().RegId());
+        codegen_.DumpCoreRegister(output_, location.reg());
       }
     } else if (location.IsConstant()) {
       output_ << "constant";