[gimp/gimp-2-10] plug-ins: fix two harmless compiler warnings

[Michael Natterer <mitch src gnome org>]

commit c2f4a47f4d22c5826c3f9d264423b1f87fe1c8e6
Author: Michael Natterer <mitch gimp org>
Date:   Tue Jul 2 15:22:16 2019 +0200

    plug-ins: fix two harmless compiler warnings
    
    (cherry picked from commit 738c035839369cb3ad44939b33851df71ef269c6)

 plug-ins/common/file-heif.c         | 2 ++
 plug-ins/metadata/metadata-editor.c | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/plug-ins/common/file-heif.c b/plug-ins/common/file-heif.c
index 5d69079c76..3f60b3e773 100644
--- a/plug-ins/common/file-heif.c
+++ b/plug-ins/common/file-heif.c
@@ -1226,7 +1226,9 @@ save_dialog (SaveParams *params)
   GtkWidget *label;
   GtkWidget *lossless_button;
   GtkWidget *frame;
+#ifdef HAVE_LIBHEIF_1_4_0
   GtkWidget *profile_button;
+#endif
   GtkWidget *quality_slider;
   gboolean   run = FALSE;
 
diff --git a/plug-ins/metadata/metadata-editor.c b/plug-ins/metadata/metadata-editor.c
index 13e38526d2..69dd83fa32 100644
--- a/plug-ins/metadata/metadata-editor.c
+++ b/plug-ins/metadata/metadata-editor.c
@@ -611,7 +611,7 @@ remove_substring (const gchar *string,
       gchar *p = strstr (string, substring);
       if (p)
         {
-          strcpy (p, p + strlen (substring));
+          strcpy (p, p + (gint) strlen (substring));
         }
     }
 }