Remove unnecessary try catch

app/src/main/java/chat/rocket/android/chatrooms/viewmodel/ChatRoomsViewModel.kt

@@ -23,7 +23,6 @@ import com.shopify.livedataktx.nonNull
 import kotlinx.coroutines.experimental.*
 import kotlinx.coroutines.experimental.android.UI
 import timber.log.Timber
-import java.lang.IllegalArgumentException
 
 class ChatRoomsViewModel(
     private val connectionManager: ConnectionManager,
@@ -43,7 +42,6 @@ class ChatRoomsViewModel(
 
             return@switchMap if (query.isSearch()) {
                 this@ChatRoomsViewModel.query.wrap(runContext) { _, data: MutableLiveData<RoomsModel> ->
-                    try {
                     val string = (query as Query.Search).query
 
                     // debounce, to not query while the user is writing
@@ -58,9 +56,6 @@ class ChatRoomsViewModel(
                     }.ifNull {
                         data.postValue(rooms)
                     }
-                    } catch (ignore: CancellationException) {
-
-                    }
                 }
             } else {
                 repository.getChatRooms(query.asSortingOrder())