Revert of [turbofan] Use PlainPrimitiveToNumber whenever possible.

test/cctest/compiler/test-js-typed-lowering.cc

Index: test/cctest/compiler/test-js-typed-lowering.cc
diff --git a/test/cctest/compiler/test-js-typed-lowering.cc b/test/cctest/compiler/test-js-typed-lowering.cc
index f51c2f256bb63d50361058c95ca8a9ea5f37a348..e23ad0cd169d091297556920d918e7378e70cc12 100644
--- a/test/cctest/compiler/test-js-typed-lowering.cc
+++ b/test/cctest/compiler/test-js-typed-lowering.cc
@@ -488,7 +488,7 @@
   for (size_t i = 0; i < arraysize(others); i++) {
     Type* t = Type::Union(Type::Number(), others[i], R.main_zone());
     Node* r = R.ReduceUnop(R.javascript.ToNumber(), t);
-    CHECK_EQ(IrOpcode::kPlainPrimitiveToNumber, r->opcode());
+    CHECK_EQ(IrOpcode::kJSToNumber, r->opcode());
   }
 }
 
@@ -1033,8 +1033,7 @@
     BinopEffectsTester B(ops[j], Type::Symbol(), Type::String());
     CHECK_EQ(ops[j + 1]->opcode(), B.result->op()->opcode());
 
-    Node* i0 =
-        B.CheckConvertedInput(IrOpcode::kPlainPrimitiveToNumber, 0, false);
+    Node* i0 = B.CheckConvertedInput(IrOpcode::kJSToNumber, 0, true);
     Node* i1 = B.CheckConvertedInput(IrOpcode::kJSToNumber, 1, true);
 
     // Inputs should be commuted.