Add a run-fail test for result::get, get rid of a FIXME. Also some random other tests, mostly xfailed.

src/test/compile-fail/issue-1451.rs

@@ -0,0 +1,23 @@
+// xfail-test
+type T = { mut f: fn@() };
+type S = { f: fn@() };
+
+fn fooS(t: S) {
+}
+
+fn fooT(t: T) {
+}
+
+fn bar() {
+}
+
+fn main() {
+    let x: fn@() = bar;
+    fooS({f: x});
+    fooS({f: bar});
+
+    let x: fn@() = bar;
+    fooT({mut f: x});
+    fooT({mut f: bar});
+}
+

src/test/compile-fail/issue-1871.rs

@@ -0,0 +1,11 @@
+// xfail-test
+fn main() {
+  let f = 42;
+
+  let _g = if f < 5 {
+      f.honk();
+  }
+  else {
+    12
+  };
+}