diff --git a/js/src/tests/browser.js b/js/src/tests/browser.js
index 9a819d380f1..17693d9c5bb 100644
--- a/js/src/tests/browser.js
+++ b/js/src/tests/browser.js
@@ -346,7 +346,7 @@ function jsTestDriverBrowserInit()
     {
       properties.version = '1.7';
     }
-    else if (properties.test.match(/^js1_8|^ecma_6/))
+    else if (properties.test.match(/^js1_8/))
     {
       properties.version = '1.8';
     }
diff --git a/js/src/tests/ecma_6/Math/acosh-approx.js b/js/src/tests/ecma_6/Math/acosh-approx.js
index 8bf837da735..630303fe8d5 100644
--- a/js/src/tests/ecma_6/Math/acosh-approx.js
+++ b/js/src/tests/ecma_6/Math/acosh-approx.js
@@ -262,7 +262,7 @@ var cosh_data = [
     [1875817529344, 28.953212876533797]
 ];
 
-for (let [x, y] of cosh_data)
+for (var [x, y] of cosh_data)
     assertNear(Math.acosh(x), y);
 
 for (var i = 0; i <= 100; i++) {
diff --git a/js/src/tests/ecma_6/Math/asinh-approx.js b/js/src/tests/ecma_6/Math/asinh-approx.js
index 09da4d89f12..bfb8eb47935 100644
--- a/js/src/tests/ecma_6/Math/asinh-approx.js
+++ b/js/src/tests/ecma_6/Math/asinh-approx.js
@@ -282,7 +282,7 @@ var sinh_data = [
     [1581915832320, 28.78280496108106]
 ];
 
-for (let [x, y] of sinh_data)
+for (var [x, y] of sinh_data)
     assertNear(Math.asinh(x), y);
 
 for (var i = 0; i <= 80; i++) {
diff --git a/js/src/tests/ecma_6/Math/atanh-approx.js b/js/src/tests/ecma_6/Math/atanh-approx.js
index 07d708badb7..41d4fd1ca95 100644
--- a/js/src/tests/ecma_6/Math/atanh-approx.js
+++ b/js/src/tests/ecma_6/Math/atanh-approx.js
@@ -269,7 +269,7 @@ var tanh_data = [
     [1e-10, 1e-10],
 ];
 
-for (let [x, y] of tanh_data)
+for (var [x, y] of tanh_data)
     assertNear(Math.atanh(x), y);
 
 assertNear(Math.atanh(+3 / 5), +Math.log(2));
diff --git a/js/src/tests/ecma_6/Math/cbrt-approx.js b/js/src/tests/ecma_6/Math/cbrt-approx.js
index f944fdf0f96..b5511753756 100644
--- a/js/src/tests/ecma_6/Math/cbrt-approx.js
+++ b/js/src/tests/ecma_6/Math/cbrt-approx.js
@@ -11,7 +11,7 @@ var cbrt_data = [
     [ Math.SQRT2, 1.1224620483093728 ]
 ];
 
-for (let [x, y] of cbrt_data)
+for (var [x, y] of cbrt_data)
     assertNear(Math.cbrt(x), y);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/Math/cosh-approx.js b/js/src/tests/ecma_6/Math/cosh-approx.js
index 14f6b7488f3..acf18668df9 100644
--- a/js/src/tests/ecma_6/Math/cosh-approx.js
+++ b/js/src/tests/ecma_6/Math/cosh-approx.js
@@ -269,7 +269,7 @@ var cosh_data = [
     [28.953212876533797, 1875817529343.9976],
 ];
 
-for (let [x, y] of cosh_data)
+for (var [x, y] of cosh_data)
     assertNear(Math.cosh(x), y);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/Math/expm1-approx.js b/js/src/tests/ecma_6/Math/expm1-approx.js
index 7d5826599c0..35d45541db0 100644
--- a/js/src/tests/ecma_6/Math/expm1-approx.js
+++ b/js/src/tests/ecma_6/Math/expm1-approx.js
@@ -18,7 +18,7 @@ var expm1_data = [
     [ 0.0000031404608812881633, 0.0000031404658125405988 ]
 ];
 
-for (let [x, y] of expm1_data)
+for (var [x, y] of expm1_data)
     assertNear(Math.expm1(x), y);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/Math/hypot-exact.js b/js/src/tests/ecma_6/Math/hypot-exact.js
index 4b78746c3e7..6f37b6607e5 100644
--- a/js/src/tests/ecma_6/Math/hypot-exact.js
+++ b/js/src/tests/ecma_6/Math/hypot-exact.js
@@ -2,7 +2,7 @@
 
 // If any argument is +∞, the result is +∞.
 // If any argument is −∞, the result is +∞.
-for (let inf of [Infinity, -Infinity]) {
+for (var inf of [Infinity, -Infinity]) {
     assertEq(Math.hypot(inf, 0), Infinity);
     assertEq(Math.hypot(0, inf), Infinity);
     assertEq(Math.hypot(inf, inf), Infinity);
diff --git a/js/src/tests/ecma_6/Math/log1p-approx.js b/js/src/tests/ecma_6/Math/log1p-approx.js
index 595a48ba162..f1d120af688 100644
--- a/js/src/tests/ecma_6/Math/log1p-approx.js
+++ b/js/src/tests/ecma_6/Math/log1p-approx.js
@@ -14,7 +14,7 @@ var log1p_data = [
     [ 0.011404608812881634, 0.011340066517988035 ],
 ];
 
-for (let [x, y] of log1p_data)
+for (var [x, y] of log1p_data)
     assertNear(Math.log1p(x), y);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/Math/sinh-approx.js b/js/src/tests/ecma_6/Math/sinh-approx.js
index 14e68cb5074..415110d92ea 100644
--- a/js/src/tests/ecma_6/Math/sinh-approx.js
+++ b/js/src/tests/ecma_6/Math/sinh-approx.js
@@ -289,7 +289,7 @@ var sinh_data = [
     [28.78280496108106,  1581915832319.9973]
 ];
 
-for (let [x, y] of sinh_data)
+for (var [x, y] of sinh_data)
     assertNear(Math.sinh(x), y);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/Math/tanh-approx.js b/js/src/tests/ecma_6/Math/tanh-approx.js
index 6829d9251c2..dd9bf0e91cc 100644
--- a/js/src/tests/ecma_6/Math/tanh-approx.js
+++ b/js/src/tests/ecma_6/Math/tanh-approx.js
@@ -271,7 +271,7 @@ var tanh_data = [
     [1e-10, 1e-10],
 ];
 
-for (let [x, y] of tanh_data)
+for (var [x, y] of tanh_data)
     assertNear(Math.tanh(y), x);
 
 reportCompare(0, 0, "ok");
diff --git a/js/src/tests/ecma_6/shell.js b/js/src/tests/ecma_6/shell.js
index 219aa24f631..e69de29bb2d 100644
--- a/js/src/tests/ecma_6/shell.js
+++ b/js/src/tests/ecma_6/shell.js
@@ -1,12 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
-/*
- * Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/licenses/publicdomain/
- */
-
-// explicitly turn on js185
-if (typeof version != 'undefined')
-{
-  version(185);
-}
-