Fix SequenceReference definitions.

OpenRA.Mods.Common/Traits/Render/LeavesTrails.cs

@@ -20,6 +20,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 	[Desc("Renders a sprite effect when leaving a cell.")]
 	public class LeavesTrailsInfo : ConditionalTraitInfo
 	{
+		[FieldLoader.Require]
 		public readonly string Image = null;
 
 		[SequenceReference("Image")]

OpenRA.Mods.Common/Traits/Render/WithDeathAnimation.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 	[Desc("This actor has a death animation.")]
 	public class WithDeathAnimationInfo : ConditionalTraitInfo, Requires<RenderSpritesInfo>
 	{
-		[SequenceReference(null, true)]
+		[SequenceReference(prefix: true)]
 		[Desc("Sequence prefix to play when this actor is killed by a warhead.")]
 		public readonly string DeathSequence = "die";
 

OpenRA.Mods.Common/Traits/Render/WithRepairOverlay.cs

@@ -18,7 +18,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 	[Desc("Displays an overlay when the building is being repaired by the player.")]
 	public class WithRepairOverlayInfo : PausableConditionalTraitInfo, Requires<RenderSpritesInfo>, Requires<BodyOrientationInfo>
 	{
-		[SequenceReference("Image")]
+		[SequenceReference]
 		[Desc("Sequence to use upon repair beginning.")]
 		public readonly string StartSequence = null;
 
@@ -26,7 +26,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 		[Desc("Sequence name to play once during repair intervals or repeatedly if a start sequence is set.")]
 		public readonly string Sequence = "active";
 
-		[SequenceReference("Image")]
+		[SequenceReference]
 		[Desc("Sequence to use after repairing has finished.")]
 		public readonly string EndSequence = null;