rollup merge of #20976: jbcrail/rm-unused-import

The BorrowFrom trait was unused by the tests.

diff --git a/src/libcollections/btree/map.rs b/src/libcollections/btree/map.rs
index 3e1533dd35f598aad43903e14b74774627c0af14..6c3767b011158403bed037a173487c8a129a97b7 100644 (file)
--- a/src/libcollections/btree/map.rs
+++ b/src/libcollections/btree/map.rs
@@ -1422,7 +1422,6 @@ pub fn entry<'a>(&'a mut self, mut key: K) -> Entry<'a, K, V> {
 #[cfg(test)]
 mod test {
     use prelude::*;
-    use std::borrow::BorrowFrom;
 
     use super::{BTreeMap, Occupied, Vacant};