Remove base::is_*assignable as these are now in the linux sysroot.

base/template_util_unittest.cc

Index: base/template_util_unittest.cc
diff --git a/base/template_util_unittest.cc b/base/template_util_unittest.cc
index 921596474b6d9a38991506396a1c64148025885d..e34a25b0428b4f8ef9e9d001978116aa5adb3cdb 100644
--- a/base/template_util_unittest.cc
+++ b/base/template_util_unittest.cc
@@ -30,39 +30,6 @@ static_assert(!is_non_const_reference<const int&>::value,
               "IsNonConstReference");
 static_assert(is_non_const_reference<int&>::value, "IsNonConstReference");
 
-class AssignParent {};
-class AssignChild : AssignParent {};
-
-// is_assignable<Type1, Type2>
-static_assert(!is_assignable<int, int>::value, "IsAssignable");  // 1 = 1;
-static_assert(!is_assignable<int, double>::value, "IsAssignable");
-static_assert(is_assignable<int&, int>::value, "IsAssignable");
-static_assert(is_assignable<int&, double>::value, "IsAssignable");
-static_assert(is_assignable<int&, int&>::value, "IsAssignable");
-static_assert(is_assignable<int&, int const&>::value, "IsAssignable");
-static_assert(!is_assignable<int const&, int>::value, "IsAssignable");
-static_assert(!is_assignable<AssignParent&, AssignChild>::value,
-              "IsAssignable");
-static_assert(!is_assignable<AssignChild&, AssignParent>::value,
-              "IsAssignable");
-
-struct AssignCopy {};
-struct AssignNoCopy {
-  AssignNoCopy& operator=(AssignNoCopy&&) { return *this; }
-  AssignNoCopy& operator=(const AssignNoCopy&) = delete;
-};
-struct AssignNoMove {
-  AssignNoMove& operator=(AssignNoMove&&) = delete;
-  AssignNoMove& operator=(const AssignNoMove&) = delete;
-};
-
-static_assert(is_copy_assignable<AssignCopy>::value, "IsCopyAssignable");
-static_assert(!is_copy_assignable<AssignNoCopy>::value, "IsCopyAssignable");
-
-static_assert(is_move_assignable<AssignCopy>::value, "IsMoveAssignable");
-static_assert(is_move_assignable<AssignNoCopy>::value, "IsMoveAssignable");
-static_assert(!is_move_assignable<AssignNoMove>::value, "IsMoveAssignable");
-
 // A few standard types that definitely support printing.
 static_assert(internal::SupportsOstreamOperator<int>::value,
               "ints should be printable");