Fix video playback to work with D2k VQAs

OpenRA.Game/FileFormats/Format80.cs

@@ -74,6 +74,9 @@ namespace OpenRA.FileFormats
 					var count = ((i & 0x70) >> 4) + 3;
 					var rpos = ((i & 0xf) << 8) + secondByte;
 
+					if (destIndex + count > dest.Length)
+						return destIndex;
+
 					ReplicatePrevious(dest, destIndex, destIndex - rpos, count);
 					destIndex += count;
 				}

OpenRA.Mods.Common/Widgets/Logic/AssetBrowserLogic.cs

@@ -304,7 +304,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			if (!GlobalFileSystem.Exists(filename))
 				return false;
 
-			if (Path.GetExtension(filename).ToLower() == ".vqa")
+			if (Path.GetExtension(filename.ToLowerInvariant()) == ".vqa")
 			{
 				player = panel.Get<VqaPlayerWidget>("PLAYER");
 				currentFilename = filename;