I have same issue.
For Editer, there is no error message, but on Android “Lighting Needs to be Rebuilt” message.
Here are log messages for “DumpUnbuiltLightIteractions”
[2019.05.16-10.26.27:643][447]DumpUnbuiltLightIteractions
[2019.05.16-10.26.27:643][447]Lights with unbuilt interactions: 6
[2019.05.16-10.26.27:643][447] Light DirectionalLight3_1
[2019.05.16-10.26.27:643][447] Light PointLight2
[2019.05.16-10.26.27:643][447] Light PointLight3
[2019.05.16-10.26.27:643][447] Light PointLight4
[2019.05.16-10.26.27:643][447] Light PointLight5
[2019.05.16-10.26.27:643][447] Light PointLight6
[2019.05.16-10.26.27:643][447]
[2019.05.16-10.26.27:643][447]Primitives with unbuilt interactions: 14
[2019.05.16-10.26.27:643][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_7
[2019.05.16-10.26.27:643][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_9
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_8
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_6
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_5
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_4
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_3
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_2
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_13
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_10
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_1
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_0
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_12
[2019.05.16-10.26.27:644][447] Primitive FoliageInstancedStaticMeshComponent /Game/Environment/BG_Levels/Plant_Level_BG_3x3.Plant_Level_BG_3x3:PersistentLevel.InstancedFoliageActor_0.FoliageInstancedStaticMeshComponent_11
[2019.05.16-10.26.27:644][447]LogSlate: FSceneViewport::OnFocusLost() reason 2