X87: Initialize CodeStubInterfaceDescriptor in the constructor.

src/x87/lithium-x87.cc

Index: src/x87/lithium-x87.cc
diff --git a/src/x87/lithium-x87.cc b/src/x87/lithium-x87.cc
index f93ed6287c0913fdb67a1fc192049cce64b11f6b..61aebdf7d80e2344b1b642db01e8d82646c8cee5 100644
--- a/src/x87/lithium-x87.cc
+++ b/src/x87/lithium-x87.cc
@@ -2490,8 +2490,7 @@ LInstruction* LChunkBuilder::DoParameter(HParameter* instr) {
     return DefineAsSpilled(result, spill_index);
   } else {
     DCHECK(info()->IsStub());
-    CodeStubInterfaceDescriptor descriptor;
-    info()->code_stub()->InitializeInterfaceDescriptor(&descriptor);
+    CodeStubInterfaceDescriptor descriptor(info()->code_stub());
     int index = static_cast<int>(instr->index());
     Register reg = descriptor.GetEnvironmentParameterRegister(index);
     return DefineFixed(result, reg);