patch 8.0.1356: using simalt in a GUIEnter autocommand inserts characters

Problem:    Using simalt in a GUIEnter autocommand inserts strange characters.
            (Chih-Long Chang)
Solution:   Ignore K_NOP in Insert mode. (closes #2379)
diff --git a/src/edit.c b/src/edit.c
index d960de3..bf2cf31 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -781,7 +781,7 @@
 #endif
 
 	/*
-	 * Get a character for Insert mode.  Ignore K_IGNORE.
+	 * Get a character for Insert mode.  Ignore K_IGNORE and K_NOP.
 	 */
 	if (c != K_CURSORHOLD)
 	    lastc = c;		/* remember the previous char for CTRL-D */
@@ -798,7 +798,7 @@
 	    do
 	    {
 		c = safe_vgetc();
-	    } while (c == K_IGNORE);
+	    } while (c == K_IGNORE || c == K_NOP);
 
 #ifdef FEAT_AUTOCMD
 	/* Don't want K_CURSORHOLD for the second key, e.g., after CTRL-V. */
diff --git a/src/ex_getln.c b/src/ex_getln.c
index 02d03b4..4202b03 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -417,12 +417,12 @@
 
 	cursorcmd();		/* set the cursor on the right spot */
 
-	/* Get a character.  Ignore K_IGNORE, it should not do anything, such
-	 * as stop completion. */
+	/* Get a character.  Ignore K_IGNORE and K_NOP, they should not do
+	 * anything, such as stop completion. */
 	do
 	{
 	    c = safe_vgetc();
-	} while (c == K_IGNORE);
+	} while (c == K_IGNORE || c == K_NOP);
 
 	if (KeyTyped)
 	{
diff --git a/src/version.c b/src/version.c
index 0be4be4..50e3f16 100644
--- a/src/version.c
+++ b/src/version.c
@@ -772,6 +772,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1356,
+/**/
     1355,
 /**/
     1354,