Set ICSharpCode.Build.Tasks back to .NET 2.0.

Prevent crash when OnProjectFinished is called without matching OnProjectStarted.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/branches/dotnet4@4101 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Libraries/ICSharpCode.Build.Tasks/Project/ICSharpCode.Build.Tasks.csproj

@@ -18,7 +18,7 @@
     <TreatWarningsAsErrors>false</TreatWarningsAsErrors>
     <RunCodeAnalysis>False</RunCodeAnalysis>
     <SourceAnalysisOverrideSettingsFile>C:\Users\Daniel\AppData\Roaming\ICSharpCode/SharpDevelop3.0\Settings.SourceAnalysis</SourceAnalysisOverrideSettingsFile>
-    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v2.0</TargetFrameworkVersion>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <OutputPath>..\..\..\..\bin\</OutputPath>

src/Main/Base/Project/Src/Editor/ITextEditor.cs

@@ -64,7 +64,7 @@ namespace ICSharpCode.SharpDevelop.Editor
 		void ShowCompletionWindow(ICompletionItemList data);
 		
 		/// <summary>
-		/// Open a new insight window showing the specific insight items.
+		/// Open a new insight window showing the specified insight items.
 		/// </summary>
 		/// <param name="items">The insight items to show in the window.
 		/// If this property is null or an empty list, the insight window will not be shown.</param>

src/Main/Base/Project/Src/Project/MSBuildEngine.cs

@@ -342,7 +342,10 @@ namespace ICSharpCode.SharpDevelop.Project
 			void OnProjectFinished(object sender, ProjectFinishedEventArgs e)
 			{
 				FlushCurrentError();
-				worker.projectFiles.Pop();
+				// it's possible that MSBuild raises ProjectFinished without a matching
+				// ProjectStarted - e.g. if an additional import is missing
+				if (worker.projectFiles.Count > 0)
+					worker.projectFiles.Pop();
 			}
 			
 			string activeTaskName;