Cannot pass "service-type" argument to getAccounts()

While improving lp:ubuntu-sdk-tutorials to use a specific service to authenticate, I bumped into this error when launching the html5-example-online-accounts-facebook-albums example:

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WebApps API message received: {"target":"ubuntu-webapps-binding-call","name":"OnlineAccounts.getAccounts","args":"[{\"provider\":\"facebook\",\"service-type\":\"oa-2\"}]","callback":{"callbackid":"ubuntu-webapps-api0.5118796625174582"}}
Error while creating object: Ubuntu.OnlineAccounts.AccountServiceModel : [{"lineNumber":1,"columnNumber":85,"fileName":"file:///usr/lib/x86_64-linux-gnu/qt5/qml/Ubuntu/UnityWebApps/inline","message":"Expected token `:'"},{"lineNumber":1,"columnNumber":90,"fileName":"file:///usr/lib/x86_64-linux-gnu/qt5/qml/Ubuntu/UnityWebApps/inline","message":"Expected token `,'"}]
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When I modify the code to use "service" instead of "service-type", it works:

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WebApps API message received: {"target":"ubuntu-webapps-binding-call","name":"OnlineAccounts.getAccounts","args":"[{\"provider\":\"facebook\",\"service\":\"com.ubuntu.developer.knitzsche.oa-2_oa-2\"}]","callback":{"callbackid":"ubuntu-webapps-api0.0970717747695744"}}
account-service-model.cpp 286 update
account-service.cpp 100 setObjectHandle Accounts::AccountService(0x2bd6660)
{"accountId":132,"displayName":"mardyXXX","enabled":true,"provider":{"displayName":"Facebook","iconName":"facebook","id":"facebook"},"service":{"displayName":"Facebook","iconName":"facebook","id":"com.ubuntu.developer.knitzsche.oa-2_oa-2"},"serviceEnabled":true}
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The data passed to the filters should be completely transparent for unity-webapps-qml, but it appears that it's actually doing something with it. I wonder, maybe it's trying to parse the expression and fails because of the "-" sign in "service-type"?