fix crash after unplugging USB while in image viewer plugin.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@28211 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/imageviewer/imageviewer.c

@@ -403,9 +403,6 @@ void cb_progress(int current, int total)
 #define VSCROLL (LCD_HEIGHT/8)
 #define HSCROLL (LCD_WIDTH/10)
 
-#define ZOOM_IN  100 /* return codes for below function */
-#define ZOOM_OUT 101
-
 /* Pan the viewing window right - move image to the left and fill in
    the right-hand side */
 static void pan_view_right(struct image_info *info)

apps/plugins/imageviewer/imageviewer.h

@@ -382,9 +382,14 @@
 #define MIN_MEM 120000
 
 /* State code for output with return. */
-#define PLUGIN_OTHER    10
-#define PLUGIN_ABORT    11
-#define PLUGIN_OUTOFMEM 12
+enum {
+    PLUGIN_OTHER = 0x200,
+    PLUGIN_ABORT,
+    PLUGIN_OUTOFMEM,
+
+    ZOOM_IN,
+    ZOOM_OUT,
+};
 
 #if (CONFIG_PLATFORM & PLATFORM_NATIVE) && defined(HAVE_DISK_STORAGE)
 #define DISK_SPINDOWN