Chrome v31.0.1650.57 broke my packaged app webviews

Question

I have a packaged app that requires me to be able to view saved, offlined web pages. These pages are downloaded from my server when the user is online and saved to the HTML5 filesystem so that they can be viewed offline. These are pages that cannot be packaged with the app. I have been using a webview to display this content in my app and this worked fine until the Chrome browser updated to v31.0.1650.57 (Nov. 9, 2013 build). Now I am getting 'ERR_FILE_NOT_FOUND' even though the content is definitely at the provided filesystem URL. The webviews still work fine on my two Chromebooks - an Acer running v29 and an HP running v30 - unless I go into developer mode and run in beta (which is v31.0.1650.57) instead of stable.

My question is what changed and how I fix it? Has Chrome tightened up the security to the point where I'll no longer be able to view these offlined web pages? Have new permissions been added that I need to include in my manifest to get my webviews to work again? I already have permissions for 'webview', 'unlimitedStorage', and the appropriate URL permissions for downloading the pages from my server.

My application is supposed to be given to the client around the first of December so this is a major surprise. Thankfully it didn't happen after the app went live.

Thanks in advance for your help.

*Update - I should point out that viewing an external URL such as 'http://stackoverflow.com' works fine. It is the filesystem URLs (filesystem:chrome-extension://[appId]/[pathToFile]) that are no longer working.

**Update 2 - Google has updated their 'webview' docs (https://developer.chrome.com/apps/tags/webview) but I still haven't been able to load filesystem URLs.

Answer 1

Perhaps this addresses your question? https://plus.sandbox.google.com/100132233764003563318/posts/hsNTHvbvEdo