Update JS unit tests for share dialog (WIP)

apps/files_sharing/js/sharetabview.js

apps/files_sharing/tests/js/shareSpec.js

core/js/core.json

core/js/share.js

core/js/shareconfigmodel.js

core/js/sharedialoglinkshareview.js

core/js/tests/specs/shareSpec.js

core/js/tests/specs/sharedialogviewSpec.js

core/js/tests/specs/shareitemmodelSpec.js

tests/karma.config.js