Enable noexcept on Windows, use for a few move constructors.

base/containers/flat_map.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_CONTAINERS_FLAT_MAP_H_
 #define BASE_CONTAINERS_FLAT_MAP_H_
 
 #include <utility>
 
 #include "base/containers/flat_tree.h"
@@ skipping 127 matching lines @@
   flat_map();
   explicit flat_map(const Compare& comp);
 
   // Not stable in the presence of duplicates in the initializer list.
   template <class InputIterator>
   flat_map(InputIterator first,
            InputIterator last,
            const Compare& comp = Compare());
 
   flat_map(const flat_map&);
-  flat_map(flat_map&&);
+  flat_map(flat_map&&) noexcept;
 
   // Not stable in the presence of duplicates in the initializer list.
   flat_map(std::initializer_list<value_type> ilist,
            const Compare& comp = Compare());
 
   ~flat_map();
 
   // --------------------------------------------------------------------------
   // Assignments.
   //
@@ skipping 38 matching lines @@
 template <class InputIterator>
 flat_map<Key, Mapped, Compare>::flat_map(InputIterator first,
                                          InputIterator last,
                                          const Compare& comp)
     : tree(first, last, comp) {}
 
 template <class Key, class Mapped, class Compare>
 flat_map<Key, Mapped, Compare>::flat_map(const flat_map&) = default;
 
 template <class Key, class Mapped, class Compare>
-flat_map<Key, Mapped, Compare>::flat_map(flat_map&&) = default;
+flat_map<Key, Mapped, Compare>::flat_map(flat_map&&) noexcept = default;

[brucedawson, 2017/03/22 21:39:05]

That reads weird, as if you are setting noexcept to the default. But, such is
this crazy language we use.

 
 template <class Key, class Mapped, class Compare>
 flat_map<Key, Mapped, Compare>::flat_map(
     std::initializer_list<value_type> ilist,
     const Compare& comp)
     : flat_map(std::begin(ilist), std::end(ilist), comp) {}
 
 template <class Key, class Mapped, class Compare>
 flat_map<Key, Mapped, Compare>::~flat_map() = default;
 
@@ skipping 39 matching lines @@
 // General operations.
 
 template <class Key, class Mapped, class Compare>
 void flat_map<Key, Mapped, Compare>::swap(flat_map& other) {
   tree::swap(other);
 }
 
 }  // namespace base
 
 #endif  // BASE_CONTAINERS_FLAT_MAP_H_