Fixed exception when "Find references" finds a result in unsaved Designer.cs file.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/branches/3.0@3657 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Main/Base/Project/Src/Gui/Pads/SearchResultPad/SearchResultMatch.cs

@@ -64,12 +64,12 @@ namespace SearchAndReplace
 		
 		public virtual TextLocation GetStartPosition(IDocument document)
 		{
-			return document.OffsetToPosition(Offset);
+			return document.OffsetToPosition(Math.Min(Offset, document.TextLength));
 		}
 		
 		public virtual TextLocation GetEndPosition(IDocument document)
 		{
-			return document.OffsetToPosition(Offset + Length);
+			return document.OffsetToPosition(Math.Min(Offset + Length, document.TextLength));
 		}
 		
 		/// <summary>

src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs

@@ -243,11 +243,14 @@ namespace ICSharpCode.SharpDevelop.Refactoring
 		#region Common helper functions
 		public static ProvidedDocumentInformation GetDocumentInformation(string fileName)
 		{
-			foreach (IViewContent content in WorkbenchSingleton.Workbench.ViewContentCollection) {
-				if (content is ITextEditorControlProvider &&
-				    FileUtility.IsEqualFileName(content.PrimaryFileName, fileName))
-				{
-					return new ProvidedDocumentInformation(((ITextEditorControlProvider)content).TextEditorControl.Document, fileName, 0);
+			OpenedFile file = FileService.GetOpenedFile(fileName);
+			if (file != null) {
+				IFileDocumentProvider documentProvider = file.CurrentView as IFileDocumentProvider;
+				if (documentProvider != null) {
+					IDocument document = documentProvider.GetDocumentForFile(file);
+					if (document != null) {
+						return new ProvidedDocumentInformation(document, fileName, 0);
+					}
 				}
 			}
 			ITextBufferStrategy strategy = StringTextBufferStrategy.CreateTextBufferFromFile(fileName);