Fix input method handler to be reset when editor resets
Fix input method handler to be reset when editor resets

RevBy: TrustMe

Forward ported from 0.80 branch

RHawkeyed/plugins,develersrl/maliit-demo-qml,maliit/plugins,develersrl/maliit-demo-qml,RHawkeyed/plugins,maliit/plugins,RHawkeyed/plugins,KDE/plasma-maliit-plugins,maliit/plugins,RHawkeyed/plugins,KDE/plasma-maliit-plugins,KDE/plasma-maliit-plugins,maliit/plugins,RHawkeyed/plugins,develersrl/maliit-demo-qml,KDE/plasma-maliit-plugins,develersrl/maliit-demo-qml