Bug 757678 turned off the indexeddb warningQuota for desktop apps, and bug 711358 turned it off for b2g apps. It should also be turned off for Android web apps. Looks like an easy four-line (or so) patch, judging from the patch attached to bug 757678.
Hm, I think that the 'offline-app' permission should also be given to webapps? At least that's included in the context for https://hg.mozilla.org/integration/mozilla-inbound/rev/08d44c70e1cb (which fixed bug 757678, this bug's equivalent for desktop web apps).
Created attachment 675250 [details] [diff] [review] Proposed patch to match desktop webapp permissions.
cscott - You will need to convert the patch into something a check-in helper can land. If Wes has time, maybe he will just make the changes locally and land it. If that is the case, Wes only needs your name and email.
Tip: you can use git show -M -C --binary --format="# HG changeset patch%n# User %an <%ae>%n%B" -U8 to export a patch that looks like it came from hg
Whoops. Lost this for a bit, but pushed it now https://hg.mozilla.org/integration/mozilla-inbound/rev/123cb677c197