patch 8.0.0522: Win32: when 'clipboard' is "unnamed" yyp does not work

Problem:    MS-Windows: when 'clipboard' is "unnamed" yyp does not work in a
            :global command.
Solution:   When setting the clipboard was postponed, do not clear the
            register.
diff --git a/src/ui.c b/src/ui.c
index 0bd2edc..8691ab7 100644
--- a/src/ui.c
+++ b/src/ui.c
@@ -392,8 +392,6 @@
 
 #if defined(FEAT_CLIPBOARD) || defined(PROTO)
 
-static void clip_copy_selection(VimClipboard *clip);
-
 /*
  * Selection stuff using Visual mode, for cutting and pasting text to other
  * windows.
@@ -569,7 +567,8 @@
  * considerably.
  */
 static int global_change_count = 0; /* if set, inside a start_global_changes */
-static int clipboard_needs_update; /* clipboard needs to be updated */
+static int clipboard_needs_update = FALSE; /* clipboard needs to be updated */
+static int clip_did_set_selection = TRUE;
 
 /*
  * Save clip_unnamed and reset it.
@@ -590,6 +589,16 @@
 }
 
 /*
+ * Return TRUE if setting the clipboard was postponed, it already contains the
+ * right text.
+ */
+    int
+is_clipboard_needs_update()
+{
+    return clipboard_needs_update;
+}
+
+/*
  * Restore clip_unnamed and set the selection when needed.
  */
     void
@@ -619,6 +628,7 @@
 	    }
 	}
     }
+    clipboard_needs_update = FALSE;
 }
 
 /*