patch 8.0.1618: color Grey50 is missing in the compiled-in table

Problem:    Color Grey50, used for ToolbarLine, is missing in the compiled-in
            table.
Solution:   Add the color to the list. (Kazunobu Kuriyama)

src/term.c

@@ -3642,7 +3642,7 @@ swapping_screen(void)
     return (full_screen && *T_TI != NUL);
 }
 
-#ifdef FEAT_MOUSE
+#if defined(FEAT_MOUSE) || defined(PROTO)
 /*
  * setmouse() - switch mouse on/off depending on current mode and 'mouse'
  */
@@ -6805,6 +6805,7 @@ gui_get_color_cmn(char_u *name)
 	    {(char_u *)"green",		RGB(0x00, 0xFF, 0x00)},
 	    {(char_u *)"grey",		RGB(0xBE, 0xBE, 0xBE)},
 	    {(char_u *)"grey40",	RGB(0x66, 0x66, 0x66)},
+	    {(char_u *)"grey50",	RGB(0x7F, 0x7F, 0x7F)},
 	    {(char_u *)"grey90",	RGB(0xE5, 0xE5, 0xE5)},
 	    {(char_u *)"lightblue",	RGB(0xAD, 0xD8, 0xE6)},
 	    {(char_u *)"lightcyan",	RGB(0xE0, 0xFF, 0xFF)},

src/version.c

@@ -766,6 +766,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1618,
 /**/
     1617,
 /**/