Force reclaiming decompilation memory.

src/AddIns/DisplayBindings/ILSpyAddIn/DebuggerDecompilerService.cs

@@ -25,7 +25,10 @@ namespace ICSharpCode.ILSpyAddIn
 		static DebuggerDecompilerService()
 		{
 			DebugInformation = new ConcurrentDictionary<int, DecompileInformation>();
-			ProjectService.SolutionClosed += delegate { DebugInformation.Clear(); };
+			ProjectService.SolutionClosed += delegate {
+				DebugInformation.Clear();
+				GC.Collect();
+			};
 		}
 		
 		internal static IDebuggerDecompilerService Instance { get; private set; }

src/AddIns/DisplayBindings/ILSpyAddIn/ViewContent/DecompiledViewContent.cs

@@ -95,9 +95,11 @@ namespace ICSharpCode.ILSpyAddIn
 			codeView.Dispose();
 			BookmarkManager.Added -= BookmarkManager_Added;
 			BookmarkManager.Removed -= BookmarkManager_Removed;
-			DecompileInformation data;
-			DebuggerDecompilerService.DebugInformation.TryRemove(decompiledType.MetadataToken.ToInt32(), out data);
-			data = null;
+			if (decompiledType != null) {
+				DecompileInformation data;
+				DebuggerDecompilerService.DebugInformation.TryRemove(decompiledType.MetadataToken.ToInt32(), out data);
+				data = null;
+			}
 			base.Dispose();
 		}
 		#endregion