Fix typed lowering of JSUnaryNot to work with graph reducer.

src/compiler/js-generic-lowering.cc

Index: src/compiler/js-generic-lowering.cc
diff --git a/src/compiler/js-generic-lowering.cc b/src/compiler/js-generic-lowering.cc
index a2253bf53ab2be4862da414c383d89ccfaccfbde..16fb166527d6ca1d0504dd2728ef6fecb4e1d360 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -280,7 +280,6 @@ REPLACE_RUNTIME_CALL(JSCreateGlobalContext, Runtime::kAbort)
     UNIMPLEMENTED();                               \
     return node;                                   \
   }
-REPLACE_UNIMPLEMENTED(JSToString)
 REPLACE_UNIMPLEMENTED(JSToName)
 REPLACE_UNIMPLEMENTED(JSYield)
 REPLACE_UNIMPLEMENTED(JSDebugger)
@@ -402,6 +401,12 @@ Node* JSGenericLowering::LowerJSToBoolean(Node* node) {
 }
 
 
+Node* JSGenericLowering::LowerJSToString(Node* node) {
+  ReplaceWithBuiltinCall(node, Builtins::TO_STRING, 1);
+  return node;
+}
+
+
 Node* JSGenericLowering::LowerJSToObject(Node* node) {
   ReplaceWithBuiltinCall(node, Builtins::TO_OBJECT, 1);
   return node;