Watch.zig: reintroduce ReadDirectoryChangesW after kernel32 rework

Author: jayrod246

lib/std/Build/Watch.zig

@@ -255,14 +255,25 @@ const Os = switch (builtin.os.tag) {
             overlapped: windows.OVERLAPPED,
             buffer: [64512]u8 align(@alignOf(windows.FILE_NOTIFY_INFORMATION)) = undefined,
 
+            extern "kernel32" fn ReadDirectoryChangesW(
+                hDirectory: windows.HANDLE,
+                lpBuffer: [*]align(@alignOf(windows.FILE_NOTIFY_INFORMATION)) u8,
+                nBufferLength: windows.DWORD,
+                bWatchSubtree: windows.BOOL,
+                dwNotifyFilter: windows.DWORD,
+                lpBytesReturned: ?*windows.DWORD,
+                lpOverlapped: ?*windows.OVERLAPPED,
+                lpCompletionRoutine: windows.LPOVERLAPPED_COMPLETION_ROUTINE,
+            ) callconv(windows.WINAPI) windows.BOOL;
+
             fn readChanges(self: *@This()) void {
                 const notify_filter =
                     windows.FILE_NOTIFY_CHANGE_CREATION |
                     windows.FILE_NOTIFY_CHANGE_DIR_NAME |
                     windows.FILE_NOTIFY_CHANGE_FILE_NAME |
                     windows.FILE_NOTIFY_CHANGE_LAST_WRITE |
                     windows.FILE_NOTIFY_CHANGE_SIZE;
-                const r = windows.kernel32.ReadDirectoryChangesW(self.handle, @ptrCast(&self.buffer), self.buffer.len, 0, notify_filter, null, &self.overlapped, null);
+                const r = ReadDirectoryChangesW(self.handle, @ptrCast(&self.buffer), self.buffer.len, 0, notify_filter, null, &self.overlapped, null);
                 assert(r != 0);
             }