Work around more -Wshadow warnings

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@288573 91177308-0d34-0410-b5e6-96231b3b80d8

test/libcxx/containers/sequences/vector/asan_throw.pass.cpp

@@ -41,7 +41,7 @@ private:
 class ThrowOnCopy {
 public:
     ThrowOnCopy() : should_throw(false) {}
-    explicit ThrowOnCopy(bool should_throw) : should_throw(should_throw) {}
+    explicit ThrowOnCopy(bool xshould_throw) : should_throw(xshould_throw) {}
 
     ThrowOnCopy(ThrowOnCopy const & other)
         : should_throw(other.should_throw)

test/std/algorithms/alg.modifying.operations/alg.fill/fill_n.pass.cpp

@@ -81,7 +81,7 @@ test_int_array_struct_source()
 
 struct test1 {
     test1() : c(0) { }
-    test1(char c) : c(c + 1) { }
+    test1(char xc) : c(xc + 1) { }
     char c;
 };