patch 8.1.0351: 'incsearch' for :/foo/s//<Esc> changes last search pattern

Problem:    'incsearch' for :/foo/s//<Esc> changes last search pattern.
Solution:   Save the last search pattern earlier.
diff --git a/src/ex_getln.c b/src/ex_getln.c
index c316e19..80f210a 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -271,6 +271,7 @@
 /*
  * Return TRUE when 'incsearch' highlighting is to be done.
  * Sets search_first_line and search_last_line to the address range.
+ * May change the last search pattern.
  */
     static int
 do_incsearch_highlighting(int firstc, incsearch_state_T *is_state,
@@ -470,8 +471,12 @@
     int		next_char;
     int		use_last_pat;
 
+    // Parsing range may already set the last search pattern.
+    save_last_search_pattern();
+
     if (!do_incsearch_highlighting(firstc, is_state, &skiplen, &patlen))
     {
+	restore_last_search_pattern();
 	finish_incsearch_highlighting(FALSE, is_state, TRUE);
 	return;
     }
@@ -479,6 +484,7 @@
     // If there is a character waiting, search and redraw later.
     if (char_avail())
     {
+	restore_last_search_pattern();
 	is_state->incsearch_postponed = TRUE;
 	return;
     }
@@ -493,7 +499,6 @@
 	curwin->w_cursor.lnum = search_first_line;
 	curwin->w_cursor.col = 0;
     }
-    save_last_search_pattern();
 
     // Use the previous pattern for ":s//".
     next_char = ccline.cmdbuff[skiplen + patlen];
@@ -627,10 +632,19 @@
     int	    i;
     int	    save;
 
+    // Parsing range may already set the last search pattern.
+    save_last_search_pattern();
+
     if (!do_incsearch_highlighting(firstc, is_state, &skiplen, &patlen))
+    {
+	restore_last_search_pattern();
 	return OK;
+    }
     if (patlen == 0 && ccline.cmdbuff[skiplen] == NUL)
+    {
+	restore_last_search_pattern();
 	return FAIL;
+    }
 
     if (firstc == ccline.cmdbuff[skiplen])
     {
@@ -641,7 +655,6 @@
     else
 	pat = ccline.cmdbuff + skiplen;
 
-    save_last_search_pattern();
     cursor_off();
     out_flush();
     if (c == Ctrl_G)
@@ -721,8 +734,14 @@
 {
     int		skiplen, patlen;
 
+    // Parsing range may already set the last search pattern.
+    save_last_search_pattern();
+
     if (!do_incsearch_highlighting(firstc, is_state, &skiplen, &patlen))
+    {
+	restore_last_search_pattern();
 	return FAIL;
+    }
 
     // Add a character from under the cursor for 'incsearch'.
     if (is_state->did_incsearch)