Add ICycleTiming interface plus one implementation so I can feel like I did something

BizHawk.Emulation.Common/BizHawk.Emulation.Common.csproj

@@ -91,6 +91,7 @@
     <Compile Include="Interfaces\IEmulatorServiceProvider.cs" />
     <Compile Include="Interfaces\Services\IBoardInfo.cs" />
     <Compile Include="Interfaces\Services\ICreateGameDBEntries.cs" />
+    <Compile Include="Interfaces\Services\ICycleTiming.cs" />
     <Compile Include="Interfaces\Services\ISoundProvider.cs" />
     <Compile Include="Interfaces\Services\ICodeDataLogger.cs" />
     <Compile Include="Interfaces\Services\IDebuggable.cs" />

BizHawk.Emulation.Common/Interfaces/Services/ICycleTiming.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace BizHawk.Emulation.Common
+{
+	public interface ICycleTiming
+	{
+		/// <summary>
+		/// Total elapsed emulation time relative to <see cref="ClockRate"/>
+		/// </summary>
+		long CycleCount { get; }
+		/// <summary>
+		/// Clock Rate in hz for <see cref="CycleCount"/>
+		/// </summary>
+		double ClockRate { get; }
+	}
+}

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs

@@ -19,7 +19,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 	[ServiceNotApplicable(typeof(IDriveLight), typeof(IDriveLight))]
 	public partial class Gameboy : IEmulator, IVideoProvider, ISoundProvider, ISaveRam, IStatable, IInputPollable, ICodeDataLogger,
 		IBoardInfo, IDebuggable, ISettable<Gameboy.GambatteSettings, Gameboy.GambatteSyncSettings>,
-		IGameboyCommon
+		IGameboyCommon, ICycleTiming
 	{
 		[CoreConstructor("GB", "GBC")]
 		public Gameboy(CoreComm comm, GameInfo game, byte[] file, object settings, object syncSettings, bool deterministic)
@@ -253,7 +253,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 		/// number of extra cycles we overran in the last frame
 		/// </summary>
 		private uint frameOverflow = 0;
-		public ulong CycleCount => _cycleCount;
+		public long CycleCount => (long)_cycleCount;
+		public double ClockRate => TICKSPERSECOND;
 
 		#endregion