Merge branch 'master' into 3.0.0

Conflicts:
	CHANGELOG.md
	lib/6to5/transformation/transform.js

test/fixtures/transformation/es6-default-parameters/destructuring/exec.js

@@ -0,0 +1,19 @@
+function required(msg) {
+  throw new Error(msg);
+}
+
+function sum(
+  { arr = required('arr is required') } = { arr: arr = [] },
+  length = arr.length
+) {
+  let i = 0;
+  let acc = 0;
+  for (let item of arr) {
+    if (i >= length) return acc;
+    acc += item;
+    i++;
+  }
+  return acc;
+}
+
+assert.equal(sum({arr:[1,2]}), 3);

test/fixtures/transformation/es6-let-scoping/exec-collision-array-comprehension/exec.js

@@ -0,0 +1,2 @@
+var foo = [];
+assert.deepEqual([for (foo of [1, 2, 3]) foo], [1, 2, 3]);

test/fixtures/transformation/es6-let-scoping/exec-collision-array-comprehension/options.json

@@ -0,0 +1,3 @@
+{
+  "experimental": true
+}

test/fixtures/transformation/es6-let-scoping/exec-collision-for/exec.js

@@ -0,0 +1,6 @@
+let x = 0;
+for (;;) {
+  let x = 1;
+  assert.equal(x, 1);
+  break;
+}

test/fixtures/transformation/es6-let-scoping/exec-destructuring-defaults/exec.js

@@ -0,0 +1,5 @@
+var fields = [{ name: "title" }, { name: "content" }];
+
+for (let { name, value = "Default value" } of fields) {
+  assert.equal(value, "Default value");
+}