Auto merge of #29291 - petrochenkov:privacy, r=alexcrichton

The public set is expanded with trait items, impls and their items, foreign items, exported macros, variant fields, i.e. all the missing parts. Now it's a subset of the exported set.
This is needed for https://github.com/rust-lang/rust/pull/29083 because stability annotation pass uses the public set and all things listed above need to be annotated.
Rustdoc can now be migrated to the public set as well, I guess.

Exported set is now slightly more correct with regard to exported items in blocks - 1) blocks in foreign items are considered and 2) publicity is not inherited from the block's parent - if a function is public it doesn't mean structures defined in its body are public.

r? @alexcrichton or maybe someone else

src/test/auxiliary/issue-11225-3.rs

@@ -0,0 +1,29 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+trait PrivateTrait {
+    fn private_trait_method(&self);
+}
+
+struct PrivateStruct;
+
+impl PrivateStruct {
+    fn private_inherent_method(&self) { }
+}
+
+impl PrivateTrait for PrivateStruct {
+    fn private_trait_method(&self) { }
+}
+
+#[inline]
+pub fn public_generic_function() {
+    PrivateStruct.private_trait_method();
+    PrivateStruct.private_inherent_method();
+}

src/test/run-pass/issue-11225-3.rs

@@ -0,0 +1,19 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:issue-11225-3.rs
+
+// pretty-expanded FIXME #23616
+
+extern crate issue_11225_3;
+
+pub fn main() {
+    issue_11225_3::public_generic_function();
+}