Expanded HIR --unpretty hir,identified to include HIR local id.

Having the HIR local id is useful for cases like understanding the
ReScope identifiers, which are now derived from the HIR local id, and
thus one can map an ReScope back to the HIR node, once one knows what
those local ids are.

Author: pnkfelix

src/librustc_driver/pretty.rs

@@ -423,24 +423,28 @@ impl<'hir> pprust_hir::PpAnn for IdentifiedAnnotation<'hir> {
             pprust_hir::NodeName(_) => Ok(()),
             pprust_hir::NodeItem(item) => {
                 s.s.space()?;
-                s.synth_comment(item.id.to_string())
+                s.synth_comment(format!("node_id: {} hir local_id: {}",
+                                        item.id, item.hir_id.local_id.0))
             }
             pprust_hir::NodeSubItem(id) => {
                 s.s.space()?;
                 s.synth_comment(id.to_string())
             }
             pprust_hir::NodeBlock(blk) => {
                 s.s.space()?;
-                s.synth_comment(format!("block {}", blk.id))
+                s.synth_comment(format!("block node_id: {} hir local_id: {}",
+                                        blk.id, blk.hir_id.local_id.0))
             }
             pprust_hir::NodeExpr(expr) => {
                 s.s.space()?;
-                s.synth_comment(expr.id.to_string())?;
+                s.synth_comment(format!("node_id: {} hir local_id: {}",
+                                        expr.id, expr.hir_id.local_id.0))?;
                 s.pclose()
             }
             pprust_hir::NodePat(pat) => {
                 s.s.space()?;
-                s.synth_comment(format!("pat {}", pat.id))
+                s.synth_comment(format!("pat node_id: {} hir local_id: {}",
+                                        pat.id, pat.hir_id.local_id.0))
             }
         }
     }