Add missing early-bailouts in ast traversal visitors

Instructions after an unconditional jump can be omitted.

BUG=chromium:715582
R=bradnelson@chromium.org,verwaest@chromium.org
TBR=bradnelson@chromium.org

Change-Id: Ie4f4041ed836f328955a0ff396e2dfd6adc01513
Reviewed-on: https://chromium-review.googlesource.com/487983
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44923}

src/asmjs/asm-wasm-builder.cc

@@ -225,6 +225,7 @@ class AsmWasmBuilderImpl final : public AstVisitor<AsmWasmBuilderImpl> {
       }
       RECURSE(Visit(stmt));
       if (typer_failed_) break;
+      // Not stopping when a jump statement is found.
     }
   }
 

src/ast/ast-numbering.cc

@@ -632,6 +632,7 @@ void AstNumberingVisitor::VisitStatements(ZoneList<Statement*>* statements) {
   if (statements == NULL) return;
   for (int i = 0; i < statements->length(); i++) {
     Visit(statements->at(i));
+    if (statements->at(i)->IsJump()) break;
   }
 }
 

test/mjsunit/regress/regress-715582.js

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Should not crash.
+//
+this.__defineGetter__(
+  "x", (a = (function f() { return; (function() {}); })()) => { });
+x;