lazyload_images should be enabled for IE6/IE7

[GoogleCodeExporter]

We were disabling it for those browsers in sympathy with the limited 
image-inlining support.  However we don't need to inline large images for 
lazyload; just a small blank one, so it should work fine.

Original issue reported on code.google.com by jmara...@google.com on 30 Nov 2012 at 10:20

[GoogleCodeExporter]

Actually IE7 does handle the base64 image currently needed for lazyload images. 
 However, we should serve that blank image instead from 
/mod_pagespeed_static/1.gif .  That would allow us to turn this filter on for 
IE6 & IE7.

To accomplish this, we can factor out and generalize StaticJavascriptManager.

Original comment by jmara...@google.com on 4 Dec 2012 at 5:56

[GoogleCodeExporter]

To clarify, IE6 and IE7 do not handle the inlined base64 image. There is a 
really terrible looking hack using MHTML to get this to work, see 
http://www.phpied.com/mhtml-when-you-need-data-uris-in-ie7-and-under/, but I 
agree a better solution is to use /mod_pagespeed_static/1.gif.

Original comment by j...@google.com on 4 Dec 2012 at 5:59

[GoogleCodeExporter]

Original comment by jmara...@google.com on 28 Jan 2013 at 7:20

[GoogleCodeExporter]

Resolved by r2486. The blank image is no longer inlined but instead served from 
/mod_pagespeed_static. The lazyload JS has been tested with IE6 and IE7 as well.

Original comment by j...@google.com on 12 Feb 2013 at 7:11

• Changed state: Fixed
• Added labels: Milestone-v25, release-note