First round of dead file removal

experimental/visual_studio_plugin/src/MsAd7.BaseImpl/ComUtils.cs

-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Runtime.InteropServices;
-using System.Text;
-
-namespace Google.MsAd7.BaseImpl
-{
-  public class ComUtils
-  {
-    public static Guid GuidOf(Type t) {
-      Guid result = Guid.Empty;
-
-      object[] attrs = t.GetCustomAttributes(typeof (InheritGuidAttribute),
-                                             false);
-      if(attrs.Length > 0) {
-        result = GuidOf(((InheritGuidAttribute) attrs[0]).InheritFrom);
-      }
-
-      attrs = t.GetCustomAttributes(typeof (GuidAttribute),false);
-      if (attrs.Length > 0) {
-        result = new Guid(((GuidAttribute) attrs[0]).Value);
-      } 
-      return result;
-    }
-
-    public static Guid GuidOf(object o) {
-      return GuidOf(o.GetType());
-    }
-
-    public static void RequireOk(int hr) {
-      if (hr != 0) {
-        throw new COMException("Error", hr);
-      }
-    }
-  }
-
-  public class InheritGuidAttribute : Attribute {
-    public InheritGuidAttribute(Type inheritFrom) {
-      InheritFrom = inheritFrom;
-    }
-
-    public Type InheritFrom { get; set; }
-  }
-
-
-}