Remove test update_removes_components_that_dont_exist

Historically, this test was added before the check that aborts update on missing
components (which is tested by the new test in the previous commit, as well as
elsewhere), so I think this test was only testing a bug.

src/rustup-dist/tests/dist.rs

@@ -519,28 +519,6 @@ fn upgrade() {
     });
 }
 
-#[test]
-fn update_removes_components_that_dont_exist() {
-    // On day 1 install the 'bonus' component, on day 2 its no londer a component
-    let edit = &|date: &str, pkg: &mut MockPackage| {
-        if date == "2016-02-01" {
-            let mut tpkg = pkg.targets.iter_mut().find(|p| p.target == "x86_64-apple-darwin").unwrap();
-            tpkg.components.push(MockComponent {
-                name: "bonus".to_string(),
-                target: "x86_64-apple-darwin".to_string(),
-            });
-        }
-    };
-    setup(Some(edit), false, &|url, toolchain, prefix, download_cfg, temp_cfg| {
-        change_channel_date(url, "nightly", "2016-02-01");
-        update_from_dist(url, toolchain, prefix, &[], &[], download_cfg, temp_cfg).unwrap();
-        assert!(utils::path_exists(&prefix.path().join("bin/bonus")));
-        change_channel_date(url, "nightly", "2016-02-02");
-        update_from_dist(url, toolchain, prefix, &[], &[], download_cfg, temp_cfg).unwrap();
-        assert!(!utils::path_exists(&prefix.path().join("bin/bonus")));
-    });
-}
-
 #[test]
 fn update_preserves_extensions() {
     setup(None, false, &|url, toolchain, prefix, download_cfg, temp_cfg| {