Importing rustc-1.43.0

Bug: 154947284
Change-Id: If0fb270e52b73940349534cf2d7b1b76ba095363
diff --git a/src/doc/book/listings/ch15-smart-pointers/listing-15-19/Cargo.lock b/src/doc/book/listings/ch15-smart-pointers/listing-15-19/Cargo.lock
new file mode 100644
index 0000000..a792c49
--- /dev/null
+++ b/src/doc/book/listings/ch15-smart-pointers/listing-15-19/Cargo.lock
@@ -0,0 +1,6 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "cons-list"
+version = "0.1.0"
+