[gimp-web/header-image] Add pre-caching for other header images

[Pat David <patdavid src gnome org>]

commit e6890be7eafde7c3c60b7533e20f861580a59b4d
Author: Pat David <patdavid gmail com>
Date:   Mon Jan 16 14:04:13 2017 -0600

    Add pre-caching for other header images
    
    Just looping through all the header images and loading them
    into the browser cache for later (so it'll be much faster).

 content/js/rotateHeaderImg.js |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)
---
diff --git a/content/js/rotateHeaderImg.js b/content/js/rotateHeaderImg.js
index 8cbd14b..c8d3937 100644
--- a/content/js/rotateHeaderImg.js
+++ b/content/js/rotateHeaderImg.js
@@ -103,3 +103,13 @@ if( typeof( image.license ) !== undefined ){
             break;
     }
 }
+
+//
+// Pre-Cache all the header images now
+// This will allow subsequent visits to the page to
+// call the browser-cached version of these
+//
+for( var i = 0; i < imglist.length; i++ ){
+    var img = new Image();
+    img.src = imglist[i].file;    
+}