ART: Further refactor use lists

Change-Id: I9e3219575a508ca5141d851bfcaf848302480c32
diff --git a/compiler/optimizing/nodes_test.cc b/compiler/optimizing/nodes_test.cc
index cf90bf7..5dbdc74 100644
--- a/compiler/optimizing/nodes_test.cc
+++ b/compiler/optimizing/nodes_test.cc
@@ -81,13 +81,12 @@
   entry->AddInstruction(new (&allocator) HExit());
 
   ASSERT_FALSE(parameter1->HasUses());
-  ASSERT_EQ(parameter1->ExpensiveComputeNumberOfUses(), 0u);
 
   HInstruction* to_insert = new (&allocator) HNullCheck(parameter1, 0);
   entry->InsertInstructionBefore(to_insert, parameter2);
 
   ASSERT_TRUE(parameter1->HasUses());
-  ASSERT_EQ(parameter1->ExpensiveComputeNumberOfUses(), 1u);
+  ASSERT_TRUE(parameter1->GetUses().HasOnlyOneUse());
 }
 
 /**
@@ -105,13 +104,12 @@
   entry->AddInstruction(parameter);
 
   ASSERT_FALSE(parameter->HasUses());
-  ASSERT_EQ(parameter->ExpensiveComputeNumberOfUses(), 0u);
 
   HInstruction* to_add = new (&allocator) HNullCheck(parameter, 0);
   entry->AddInstruction(to_add);
 
   ASSERT_TRUE(parameter->HasUses());
-  ASSERT_EQ(parameter->ExpensiveComputeNumberOfUses(), 1u);
+  ASSERT_TRUE(parameter->GetUses().HasOnlyOneUse());
 }
 
 }  // namespace art