Use Running Document Table to track open documents

Instead of using the ITextDocumentFactoryService component, we now use
IVsRunningDocumentTable to keep track of when files are open and closed
in the VS editor.

The main reason is that ITextDocumentFactoryService keeps track of all
ITextBuffer instances used in VS, including ITextDocument instances
loaded for temporary usage, such as the "Find in File" features.

This change ensures the number of events related to opening and closing
documents is close to zero when using "Find in Files" on large directories
or project.

This is (hopefully) the last part to fix issue #61

src/Core/Files/FullPath.cs

@@ -4,7 +4,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using VsChromium.Core.Logging;
 
 namespace VsChromium.Core.Files {
@@ -19,6 +18,13 @@ public FullPath(string path) {
       _path = path;
     }
 
+    public static FullPath? Create(string path) {
+      if (IsValid(path)) {
+        return new FullPath(path);
+      }
+      return null;
+    }
+
     public static bool IsValid(string path) {
       return PathHelpers.IsAbsolutePath(path);
     }

src/Core/Files/PathHelpers.cs

@@ -117,6 +117,10 @@ public static SplitPath SplitPrefix(string path, string prefix) {
     /// method should only be used in assertion code.
     /// </summary>
     public static bool IsAbsolutePath(string path) {
+      if (string.IsNullOrEmpty(path)) {
+        return false;
+      }
+
       // Quick & dirty check, but faster than "Path.IsPathRooted".
       var l = path.Length;
 

src/VsChromium/Views/ITextDocumentTable.cs

@@ -2,13 +2,18 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+using System;
 using System.Collections.Generic;
 using Microsoft.VisualStudio.Text;
 using VsChromium.Core.Files;
 
 namespace VsChromium.Views {
-  public interface ITextDocumentTable {
+  public interface ITextDocumentTable : IDisposable {
     ITextDocument GetOpenDocument(FullPath path);
     IList<FullPath> GetOpenDocuments();
+
+    event EventHandler<TextDocumentEventArgs> TextDocumentOpened;
+    event EventHandler<TextDocumentEventArgs> TextDocumentClosed;
+    event EventHandler<VsDocumentRenameEventArgs> TextDocumentRenamed;
   }
-}
+}

src/VsChromium/Views/TextDocumentRegistrationManager.cs

@@ -0,0 +1,42 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+using System.ComponentModel.Composition;
+using Microsoft.VisualStudio.Text;
+using VsChromium.Package;
+
+namespace VsChromium.Views {
+  [Export(typeof(IPackagePostInitializer))]
+  public class TextDocumentRegistrationManager : IPackagePostInitializer {
+    private readonly ITextDocumentTable _textDocumentTable;
+    private readonly IFileRegistrationRequestService _fileRegistrationRequestService;
+
+    [ImportingConstructor]
+    public TextDocumentRegistrationManager(ITextDocumentTable textDocumentTable, IFileRegistrationRequestService fileRegistrationRequestService) {
+      _textDocumentTable = textDocumentTable;
+      _fileRegistrationRequestService = fileRegistrationRequestService;
+    }
+
+    public int Priority { get { return 0; } }
+
+    public void Run(IVisualStudioPackage package) {
+      _textDocumentTable.TextDocumentOpened += TextDocumentFactoryServiceOnTextDocumentOpened;
+      _textDocumentTable.TextDocumentClosed += TextDocumentFactoryServiceOnTextDocumentClosed;
+      _textDocumentTable.TextDocumentRenamed += TextTextDocumentFactoryServiceOnTextDocumentRenamed;
+    }
+
+    private void TextDocumentFactoryServiceOnTextDocumentOpened(object sender, TextDocumentEventArgs textDocumentEventArgs) {
+      _fileRegistrationRequestService.RegisterTextDocument(textDocumentEventArgs.TextDocument);
+    }
+
+    private void TextDocumentFactoryServiceOnTextDocumentClosed(object sender, TextDocumentEventArgs textDocumentEventArgs) {
+      _fileRegistrationRequestService.UnregisterTextDocument(textDocumentEventArgs.TextDocument);
+    }
+
+    private void TextTextDocumentFactoryServiceOnTextDocumentRenamed(object sender, VsDocumentRenameEventArgs e) {
+      _fileRegistrationRequestService.RegisterFile(e.NewPath.Value);
+      _fileRegistrationRequestService.UnregisterFile(e.OldPath.Value);
+    }
+  }
+}