Navigate diff to editor on key press

Simple proof of concept!

Author: jcansdale

src/GitHub.VisualStudio/Views/GitHubPane/PullRequestDetailView.xaml.cs

@@ -166,6 +166,7 @@ async Task DoDiffFile(IPullRequestFileNode file, bool workingDirectory)
                 if (!workingDirectory)
                 {
                     AddBufferTag(diffViewer.RightView.TextBuffer, session, rightPath, DiffSide.Right);
+                    EnableNavigateToEditor(diffViewer.RightView, file);
                 }
 
                 if (workingDirectory)
@@ -196,6 +197,15 @@ void AddBufferTag(ITextBuffer buffer, IPullRequestSession session, string path,
             }
         }
 
+        void EnableNavigateToEditor(IWpfTextView textView, IPullRequestFileNode file)
+        {
+            textView.VisualElement.PreviewKeyDown += async (s, e) =>
+            {
+                await DoOpenFile(file, true);
+                e.Handled = true;
+            };
+        }
+
         void ShowErrorInStatusBar(string message, Exception e)
         {
             var ns = GitHub.VisualStudio.Services.DefaultExportProvider.GetExportedValue<IStatusBarNotificationService>();