Revert of Parse arrow functions at proper precedence level

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index ad60de9ca87c5acb350190919e4ad2909ea76192..8c59ce86c9fe11f4c8ed1cfb76a8ed69cfcd3f2f 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -11525,11 +11525,6 @@
 void HOptimizedGraphBuilder::VisitSpread(Spread* expr) { UNREACHABLE(); }
 
 
-void HOptimizedGraphBuilder::VisitEmptyParentheses(EmptyParentheses* expr) {
-  UNREACHABLE();
-}
-
-
 HInstruction* HOptimizedGraphBuilder::BuildThisFunction() {
   // If we share optimized code between different closures, the
   // this-function is not a constant, except inside an inlined body.