ART: Fix a failing gtest

Stricter assumptions about the state of linear scan caused a reg alloc
gtest to fail.

Change-Id: I0c568bf996ce6adefe4f000524b38acd3967421e
diff --git a/compiler/optimizing/register_allocator_test.cc b/compiler/optimizing/register_allocator_test.cc
index c307d98..182cd0e 100644
--- a/compiler/optimizing/register_allocator_test.cc
+++ b/compiler/optimizing/register_allocator_test.cc
@@ -433,18 +433,15 @@
   // Add three temps holding the same register, and starting at different positions.
   // Put the one that should be picked in the middle of the inactive list to ensure
   // we do not depend on an order.
-  LiveInterval* interval = LiveInterval::MakeInterval(&allocator, Primitive::kPrimInt);
-  interval->SetRegister(0);
+  LiveInterval* interval = LiveInterval::MakeFixedInterval(&allocator, 0, Primitive::kPrimInt);
   interval->AddRange(40, 50);
   register_allocator.inactive_.Add(interval);
 
-  interval = LiveInterval::MakeInterval(&allocator, Primitive::kPrimInt);
-  interval->SetRegister(0);
+  interval = LiveInterval::MakeFixedInterval(&allocator, 0, Primitive::kPrimInt);
   interval->AddRange(20, 30);
   register_allocator.inactive_.Add(interval);
 
-  interval = LiveInterval::MakeInterval(&allocator, Primitive::kPrimInt);
-  interval->SetRegister(0);
+  interval = LiveInterval::MakeFixedInterval(&allocator, 0, Primitive::kPrimInt);
   interval->AddRange(60, 70);
   register_allocator.inactive_.Add(interval);