Revert of MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests.

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

Index: test/unittests/compiler/instruction-sequence-unittest.cc
diff --git a/test/unittests/compiler/instruction-sequence-unittest.cc b/test/unittests/compiler/instruction-sequence-unittest.cc
index 9d17c26a5642d9d0efd12d53d01bb19fd742f58a..e61f690b4ef29adbb8bd2d0f6306fe9582be7020 100644
--- a/test/unittests/compiler/instruction-sequence-unittest.cc
+++ b/test/unittests/compiler/instruction-sequence-unittest.cc
@@ -18,6 +18,11 @@
     double_register_names_[RegisterConfiguration::kMaxFPRegisters];
 static char register_names_[10 * (RegisterConfiguration::kMaxGeneralRegisters +
                                   RegisterConfiguration::kMaxFPRegisters)];
+
+namespace {
+static int allocatable_codes[InstructionSequenceTest::kDefaultNRegs] = {
+    0, 1, 2, 3, 4, 5, 6, 7};
+}
 
 static void InitializeRegisterNames() {
   char* loc = register_names_;
@@ -80,8 +85,19 @@
   }
 }
 
-const RegisterConfiguration* InstructionSequenceTest::config() {
-  return sequence()->GetRegisterConfigurationForTesting();
+RegisterConfiguration* InstructionSequenceTest::config() {
+  if (!config_) {
+    config_.reset(new RegisterConfiguration(
+        num_general_registers_, num_double_registers_, num_general_registers_,
+        num_double_registers_, allocatable_codes, allocatable_codes,
+        kSimpleFPAliasing ? RegisterConfiguration::OVERLAP
+                          : RegisterConfiguration::COMBINE,
+        general_register_names_,
+        double_register_names_,  // float register names
+        double_register_names_,
+        double_register_names_));  // SIMD 128 register names
+  }
+  return config_.get();
 }