[turbofan] Some cleanup to the Typer.

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 78618798dde37220297a6953a21f0fdb1a8c1646..82c471fc68d2fcc0e34995e242344a885a9b39c0 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -3187,6 +3187,8 @@ void Heap::CreateInitialObjects() {
   set_nan_value(*factory->NewHeapNumber(
       std::numeric_limits<double>::quiet_NaN(), IMMUTABLE, TENURED));
   set_infinity_value(*factory->NewHeapNumber(V8_INFINITY, IMMUTABLE, TENURED));
+  set_minus_infinity_value(
+      *factory->NewHeapNumber(-V8_INFINITY, IMMUTABLE, TENURED));
 
   // The hole has not been created yet, but we want to put something
   // predictable in the gaps in the string table, so lets make that Smi zero.