add files loaded through doc(include) into dep-info

src/test/run-make/include_bytes_deps/Makefile

@@ -8,7 +8,7 @@ ifneq ($(shell uname),FreeBSD)
 ifndef IS_WINDOWS
 all:
 	$(RUSTC) --emit dep-info main.rs
-	$(CGREP) "input.txt" "input.bin" < $(TMPDIR)/main.d
+	$(CGREP) "input.txt" "input.bin" "input.md" < $(TMPDIR)/main.d
 else
 all:
 

src/test/run-make/include_bytes_deps/input.md

@@ -0,0 +1 @@
+# Hello, world!

src/test/run-make/include_bytes_deps/main.rs

@@ -8,6 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![feature(external_doc)]
+
+#[doc(include="input.md")]
+pub struct SomeStruct;
+
 pub fn main() {
     const INPUT_TXT: &'static str = include_str!("input.txt");
     const INPUT_BIN: &'static [u8] = include_bytes!("input.bin");