patch 9.0.1896: "below" virtual text doesn't work with 'rightleft'

Problem:  "below" virtual text doesn't work with 'rightleft'.
Solution: Use column from right border with 'rightleft'.

closes: #13071

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>

src/drawline.c

@@ -2011,10 +2011,8 @@ win_line(
 
 		if (wlv.n_extra == 0 ||
 			(!wlv.extra_for_textprop
-#ifdef FEAT_PROP_POPUP
 			 && !(text_prop_type != NULL &&
 			     text_prop_flags & PT_FLAG_OVERRIDE)
-#endif
 		    ))
 		{
 		    text_prop_attr = 0;
@@ -2155,6 +2153,11 @@ win_line(
 				// exactly the same.
 				start_line = text_prop_position(wp, tp,
 						    wlv.vcol,
+# ifdef FEAT_RIGHTLEFT
+						    wp->w_p_rl
+						    ? wp->w_width - wlv.col - 1
+						    :
+# endif
 						    wlv.col,
 						    &wlv.n_extra, &wlv.p_extra,
 						    &n_attr, &wlv.n_attr_skip,

src/testdir/dumps/Test_prop_below_rightleft_1.dump

@@ -0,0 +1,6 @@
+| +0&#ffffff0@50|e|d|c|b>a| +0#af5f00255&|1| @1
+| +0#0000000&@50|5+0#e000e06&|4|3|2|1| +0#af5f00255&@3
+| +0#4040ff13&@58|~
+| @58|~
+| @58|~
+| +0#0000000&@41|1|,|1| @10|A|l@1| 

src/testdir/test_textprop.vim

@@ -3087,6 +3087,23 @@ func Test_prop_with_multibyte_below()
   call StopVimInTerminal(buf)
 endfunc
 
+func Test_prop_with_text_below_rightleft()
+  CheckRunVimInTerminal
+  CheckFeature rightleft
+
+  let lines =<< trim END
+    setlocal number rightleft
+    call setline(1, 'abcde')
+    call prop_type_add('theprop', #{highlight: 'Special'})
+    call prop_add(1, 0, #{type: 'theprop', text: '12345', text_align: 'below'})
+  END
+  call writefile(lines, 'XscriptPropBelowRightleft', 'D')
+  let buf = RunVimInTerminal('-S XscriptPropBelowRightleft', #{rows: 6, cols: 60})
+  call VerifyScreenDump(buf, 'Test_prop_below_rightleft_1', {})
+
+  call StopVimInTerminal(buf)
+endfunc
+
 func Test_prop_with_text_above_empty()
   CheckRunVimInTerminal
 

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1896,
 /**/
     1895,
 /**/