Add IsManaged helper method to EF classes to match realm implementation

osu.Game/Beatmaps/BeatmapDifficulty.cs

@@ -15,6 +15,8 @@ namespace osu.Game.Beatmaps
 
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public float DrainRate { get; set; } = DEFAULT_DIFFICULTY;
         public float CircleSize { get; set; } = DEFAULT_DIFFICULTY;
         public float OverallDifficulty { get; set; } = DEFAULT_DIFFICULTY;

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -21,6 +21,8 @@ namespace osu.Game.Beatmaps
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public int BeatmapVersion;
 
         private int? onlineID;

osu.Game/Beatmaps/BeatmapMetadata.cs

@@ -20,6 +20,8 @@ namespace osu.Game.Beatmaps
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public string Title { get; set; } = string.Empty;
 
         [JsonProperty("title_unicode")]

osu.Game/Beatmaps/BeatmapSetFileInfo.cs

@@ -11,6 +11,8 @@ namespace osu.Game.Beatmaps
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public int BeatmapSetInfoID { get; set; }
 
         public int FileInfoID { get; set; }

osu.Game/Beatmaps/BeatmapSetInfo.cs

@@ -16,6 +16,8 @@ namespace osu.Game.Beatmaps
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         private int? onlineID;
 
         [Column("OnlineBeatmapSetID")]

osu.Game/Configuration/DatabasedSetting.cs

@@ -11,6 +11,8 @@ namespace osu.Game.Configuration
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public int? RulesetID { get; set; }
 
         public int? Variant { get; set; }

osu.Game/Database/IHasPrimaryKey.cs

@@ -11,5 +11,7 @@ namespace osu.Game.Database
         [JsonIgnore]
         [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
         int ID { get; set; }
+
+        bool IsManaged { get; }
     }
 }

osu.Game/IO/FileInfo.cs

@@ -10,6 +10,8 @@ namespace osu.Game.IO
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public string Hash { get; set; }
 
         public string StoragePath => Path.Combine(Hash.Remove(1), Hash.Remove(2), Hash);

osu.Game/Scoring/ScoreFileInfo.cs

@@ -11,6 +11,8 @@ namespace osu.Game.Scoring
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public int FileInfoID { get; set; }
 
         public FileInfo FileInfo { get; set; }

osu.Game/Scoring/ScoreInfo.cs

@@ -22,6 +22,8 @@ namespace osu.Game.Scoring
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public ScoreRank Rank { get; set; }
 
         public long TotalScore { get; set; }

osu.Game/Skinning/SkinFileInfo.cs

@@ -11,6 +11,8 @@ namespace osu.Game.Skinning
     {
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public int SkinInfoID { get; set; }
 
         public int FileInfoID { get; set; }

osu.Game/Skinning/SkinInfo.cs

@@ -18,6 +18,8 @@ namespace osu.Game.Skinning
 
         public int ID { get; set; }
 
+        public bool IsManaged => ID > 0;
+
         public string Name { get; set; } = string.Empty;
 
         public string Creator { get; set; } = string.Empty;