Add test for showing rmeta candidates in error

src/test/ui/crate-loading/crateresolve2.rs

@@ -0,0 +1,14 @@
+// check-fail
+
+// aux-build:crateresolve2-1.rs
+// aux-build:crateresolve2-2.rs
+// aux-build:crateresolve2-3.rs
+
+// normalize-stderr-test: "\.nll/" -> "/"
+// normalize-stderr-test: "\\\?\\" -> ""
+
+extern crate crateresolve2;
+//~^ ERROR multiple matching crates for `crateresolve2`
+
+fn main() {
+}