patch 8.2.2244: crash when making the window width negative

Problem:    Crash when making the window width of the not-current window
            negative.
Solution:   Make sure the window width is not negative. (closes #7568)
diff --git a/src/testdir/test_window_cmd.vim b/src/testdir/test_window_cmd.vim
index 51d0722..b0c5a41 100644
--- a/src/testdir/test_window_cmd.vim
+++ b/src/testdir/test_window_cmd.vim
@@ -1148,6 +1148,14 @@
   exe other_winnr .. 'resize +1'
   call assert_equal(12, winheight(other_winnr))
   call assert_equal(&lines - 10 - 3 -2, winheight(0))
+  close
+
+  vsplit
+  wincmd l
+  let other_winnr = winnr('h')
+  call assert_notequal(winnr(), other_winnr)
+  exe 'vert ' .. other_winnr .. 'resize -100'
+  call assert_equal(0, winwidth(other_winnr))
 
   %bwipe!
 endfunc
diff --git a/src/version.c b/src/version.c
index 6c6d8c6..20bd86f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2244,
+/**/
     2243,
 /**/
     2242,
diff --git a/src/window.c b/src/window.c
index 1cf795f..bea4f39 100644
--- a/src/window.c
+++ b/src/window.c
@@ -5687,6 +5687,8 @@
 	if (width == 0)
 	    width = 1;
     }
+    else if (width < 0)
+	width = 0;
 
     frame_setwidth(wp->w_frame, width + wp->w_vsep_width);