Rename all proposal plugins to -proposal- from -transform- (#6570)

packages/babel-plugin-proposal-object-rest-spread/test/fixtures/object-rest/variable-exec/exec.js

@@ -0,0 +1,22 @@
+// var { x, y, ...z } = { x: 1, y: 2, a: 3, b: 4 };
+
+// assert.equal(x, 1);
+// assert.equal(y, 2);
+// assert.deepEqual(z, { a: 3, b: 4 });
+
+// var complex = {
+//   x: { a: 1, b: 2, c: 3 },
+// };
+
+// var {
+//   x: { a: xa, ...xbc }
+// } = complex;
+
+// assert.equal(xa, 1);
+// assert.deepEqual(xbc, { b: 2, c: 3});
+
+// // own properties
+// function ownX({ ...properties }) {
+//   return properties.x;
+// }
+// assert.equal(ownX(Object.create({ x: 1 })), undefined);