Update to latest syn-1.0.16

* fill back missing NOTICE,METADATA,*LICENSE* files

Bug: 150877376
Test: make
Test: atest --host -c --include-subdirs external/rust/crates
Change-Id: Ib5df6b8fb97764214e701a888e44fab3a4245800
diff --git a/tests/repo/progress.rs b/tests/repo/progress.rs
new file mode 100644
index 0000000..28c8a44
--- /dev/null
+++ b/tests/repo/progress.rs
@@ -0,0 +1,37 @@
+use std::io::{Read, Result};
+use std::time::{Duration, Instant};
+
+pub struct Progress<R> {
+    bytes: usize,
+    tick: Instant,
+    stream: R,
+}
+
+impl<R> Progress<R> {
+    pub fn new(stream: R) -> Self {
+        Progress {
+            bytes: 0,
+            tick: Instant::now() + Duration::from_millis(2000),
+            stream,
+        }
+    }
+}
+
+impl<R: Read> Read for Progress<R> {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        let num = self.stream.read(buf)?;
+        self.bytes += num;
+        let now = Instant::now();
+        if now > self.tick {
+            self.tick = now + Duration::from_millis(500);
+            errorf!("downloading... {} bytes\n", self.bytes);
+        }
+        Ok(num)
+    }
+}
+
+impl<R> Drop for Progress<R> {
+    fn drop(&mut self) {
+        errorf!("done ({} bytes)\n", self.bytes);
+    }
+}