Fixed ArgumentNullException in CompileModifiedProjectsOnly when an IBuildable2 implementation returned null as ProjectBuildOptions.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/branches/3.0@4190 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Main/Base/Project/Src/Services/ProjectService/CompileModifiedProjectsOnly.cs

@@ -214,6 +214,7 @@ namespace ICSharpCode.SharpDevelop.Project
 			}
 			
 			Dictionary<ProjectBuildOptions, ICollection<IBuildable>> cachedBuildDependencies = new Dictionary<ProjectBuildOptions, ICollection<IBuildable>>();
+			ICollection<IBuildable> cachedBuildDependenciesForNullOptions;
 				
 			public ICollection<IBuildable> GetBuildDependencies(ProjectBuildOptions buildOptions)
 			{
@@ -222,7 +223,10 @@ namespace ICSharpCode.SharpDevelop.Project
 					result.Add(factory.GetWrapper(b));
 				}
 				lock (cachedBuildDependencies) {
+					if (buildOptions != null)
 						cachedBuildDependencies[buildOptions] = result;
+					else
+						cachedBuildDependenciesForNullOptions = result;
 				}
 				return result;
 			}
@@ -254,7 +258,8 @@ namespace ICSharpCode.SharpDevelop.Project
 					}
 					if (lastCompilationPass != null && Setting == BuildOnExecuteSetting.BuildModifiedAndDependent) {
 						lock (cachedBuildDependencies) {
-							if (cachedBuildDependencies[buildOptions].OfType<Wrapper>().Any(w=>w.WasRecompiledAfter(lastCompilationPass))) {
+							var dependencies = buildOptions != null ? cachedBuildDependencies[buildOptions] : cachedBuildDependenciesForNullOptions;
+							if (dependencies.OfType<Wrapper>().Any(w=>w.WasRecompiledAfter(lastCompilationPass))) {
 								lastCompilationPass = null;
 							}
 						}