Good news everyone!
Oneway-syncing of passwords from Mozilla Weave/Firefox Sync to Dolphin HD has now been implemented in my DolphinHD plugin for Android.
See the wiki for details
I found a way to circumvent android.webkit.WebViewDatabase .
Even as they haven't signed version 1 yet, version 1.1 will find it's way to Dolphin for signing soon.
(Well, okay. Version 1 was done yesterday. Can't expect them keep up with me.)