[turbofan] Eliminate checkpoints before return in common op reducer.

test/mjsunit/compiler/regress-628773.js

Index: test/mjsunit/compiler/regress-628773.js
diff --git a/test/message/syntactic-tail-call-in-try-try-catch-finally.js b/test/mjsunit/compiler/regress-628773.js
similarity index 52%
copy from test/message/syntactic-tail-call-in-try-try-catch-finally.js
copy to test/mjsunit/compiler/regress-628773.js
index 5b000f11817dfa2287efa7bb680b8cf121bef2ff..3c315b38283281a7f8827f1868aef0c257358f83 100644
--- a/test/message/syntactic-tail-call-in-try-try-catch-finally.js
+++ b/test/mjsunit/compiler/regress-628773.js
@@ -2,21 +2,20 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-explicit-tailcalls
-"use strict";
+// Flags: --harmony-tailcalls
 
-function f() {
-  return 1;
-}
+"use strict";
 
-function g() {
-  try {
+function foo() {
+  for  (var i = 0; i < 10000; i++) {
     try {
-      f();
+      for (var j = 0; j < 2; j++) {
+      }
+      throw 1;
     } catch(e) {
-      return continue f()  ;
+      if (typeof a == "number") return a && isNaN(b);
     }
-  } finally {
-    f();
   }
 }
+
+foo();