Issue 5383 - Add tests for the Chrome and Firefox packagers

packagerChrome.py

Index: packagerChrome.py
diff --git a/packagerChrome.py b/packagerChrome.py
index d75203d17b9e63262e69f44e5112cfc729005d8d..eb6eb1f21dcbee12d7ade95d0790ca9560d4fe14 100644
--- a/packagerChrome.py
+++ b/packagerChrome.py
@@ -43,13 +43,15 @@ def processFile(path, data, params):
 
 
 def makeIcons(files, filenames):
-    try:
-        from PIL import Image
-    except ImportError:
-        import Image
     icons = {}
     for filename in filenames:
-        width, height = Image.open(StringIO(files[filename])).size
+        try:
+            magic, width, height = struct.unpack_from('>8s8xii',
+                                                      files[filename])
+        except struct.error:
+            magic = None
+        if magic != '\x89PNG\r\n\x1a\n':
+            raise Exception(filename + ' is no valid PNG.')
         if(width != height):
             print >>sys.stderr, 'Warning: %s size is %ix%i, icon should be square' % (filename, width, height)
         icons[width] = filename