Force close app when exception occurs in FutureHelper.

core/src/main/scala/com/nutomic/ensichat/core/util/FutureHelper.scala

@@ -1,5 +1,7 @@
 package com.nutomic.ensichat.core.util
 
+import com.nutomic.ensichat.core.interfaces.Log
+
 import scala.concurrent.{ExecutionContext, Future}
 
 /**
@@ -9,11 +11,17 @@ import scala.concurrent.{ExecutionContext, Future}
  */
 object FutureHelper {
 
+  private val Tag = "FutureHelper"
+
   def apply[A](action: => A)(implicit executor: ExecutionContext): Future[A] = {
     val f = Future(action)
     f.onFailure {
       case e =>
-        throw e
+        // HACK: Android does not close app when crash occurs in background thread, and there's no
+        //       cross-platform way to execute on the foreground thread.
+        //       We use this to make sure exceptions are not hidden in the logs.
+        Log.e(Tag, "Exception in Future", e)
+        System.exit(-1)
     }
     f
   }