[libcxx] [test] Fix MSVC x64 truncation warnings with 32-bit allocator size_type/difference_type.

[STL_MSFT]

Summary

[libcxx] [test] Fix MSVC x64 truncation warnings with 32-bit allocator size_type/difference_type.

test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp
test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp
Iterate with C::size_type because that's what operator[] takes.

test/std/containers/sequences/vector/contiguous.pass.cpp
test/std/strings/basic.string/string.require/contiguous.pass.cpp
Add static_cast<typename C::difference_type> because that's what the iterator's operator+ takes.

test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp

 };
 
 int main()
 {
     C d = make<C>(5);
     test q(d, test_allocator<int>(4));
     assert(q.get_allocator() == test_allocator<int>(4));
     assert(q.size() == 5);
-    for (std::size_t i = 0; i < d.size(); ++i)
+    for (C::size_type i = 0; i < d.size(); ++i)
     {
         assert(q.front() == d[i]);
         q.pop();
     }
 }

test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp

 };
 
 int main()
 {
     C d = make<C>(5);
     test q(d, test_allocator<int>(4));
     assert(q.get_allocator() == test_allocator<int>(4));
     assert(q.size() == 5);
-    for (std::size_t i = 0; i < d.size(); ++i)
+    for (C::size_type i = 0; i < d.size(); ++i)
     {
         assert(q.top() == d[d.size() - i - 1]);
         q.pop();
     }
 }

test/std/containers/sequences/vector/contiguous.pass.cpp

 
 #include "test_allocator.h"
 #include "min_allocator.h"
 
 template <class C>
 void test_contiguous ( const C &c )
 {
     for ( size_t i = 0; i < c.size(); ++i )
-        assert ( *(c.begin() + i) == *(std::addressof(*c.begin()) + i));
+        assert ( *(c.begin() + static_cast<typename C::difference_type>(i)) == *(std::addressof(*c.begin()) + i));
 }
 
 int main()
 {
     {
     typedef int T;
     typedef std::vector<T> C;
     test_contiguous(C());

test/std/strings/basic.string/string.require/contiguous.pass.cpp

 #include "test_allocator.h"
 #include "min_allocator.h"
 
 
 template <class C>
 void test_contiguous ( const C &c )
 {
     for ( size_t i = 0; i < c.size(); ++i )
-        assert ( *(c.begin() + i) == *(std::addressof(*c.begin()) + i));
+        assert ( *(c.begin() + static_cast<typename C::difference_type>(i)) == *(std::addressof(*c.begin()) + i));
 }
 
 int main()
 {
     {
     typedef std::string S;
     test_contiguous(S());
     test_contiguous(S("1"));