rename `constraint_set` to `constraints`

also promote to its own directory, make local to nll

src/librustc_mir/borrow_check/nll/mod.rs

@@ -45,7 +45,7 @@
 crate mod type_check;
 mod universal_regions;
 
-crate mod constraint_set;
+mod constraints;
 
 use self::facts::AllFacts;
 use self::region_infer::RegionInferenceContext;

src/librustc_mir/borrow_check/nll/region_infer/graphviz.rs

@@ -17,7 +17,7 @@
 use std::borrow::Cow;
 use std::io::{self, Write};
 use super::*;
-use borrow_check::nll::constraint_set::OutlivesConstraint;
+use borrow_check::nll::constraints::OutlivesConstraint;
 
 
 impl<'tcx> RegionInferenceContext<'tcx> {

src/librustc_mir/borrow_check/nll/region_infer/mod.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use super::universal_regions::UniversalRegions;
-use borrow_check::nll::constraint_set::{
+use borrow_check::nll::constraints::{
     ConstraintIndex, ConstraintGraph, ConstraintSet, OutlivesConstraint
 };
 use borrow_check::nll::type_check::Locations;

src/librustc_mir/borrow_check/nll/type_check/constraint_conversion.rs

@@ -9,12 +9,11 @@
 // except according to those terms.
 
 use borrow_check::location::LocationTable;
-use borrow_check::nll::constraint_set::OutlivesConstraint;
+use borrow_check::nll::constraints::{ConstraintSet, OutlivesConstraint};
 use borrow_check::nll::facts::AllFacts;
 use borrow_check::nll::region_infer::{RegionTest, TypeTest};
 use borrow_check::nll::type_check::Locations;
 use borrow_check::nll::universal_regions::UniversalRegions;
-use borrow_check::nll::constraint_set::ConstraintSet;
 use rustc::infer::canonical::QueryRegionConstraint;
 use rustc::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelegate};
 use rustc::infer::region_constraints::{GenericKind, VerifyBound};

src/librustc_mir/borrow_check/nll/type_check/mod.rs

@@ -13,7 +13,7 @@
 
 use borrow_check::borrow_set::BorrowSet;
 use borrow_check::location::LocationTable;
-use borrow_check::nll::constraint_set::{ConstraintSet, OutlivesConstraint};
+use borrow_check::nll::constraints::{ConstraintSet, OutlivesConstraint};
 use borrow_check::nll::facts::AllFacts;
 use borrow_check::nll::region_infer::{ClosureRegionRequirementsExt, TypeTest};
 use borrow_check::nll::universal_regions::UniversalRegions;