Don't make the async repo duplicate the work if it's wrapped by a sync repo.

src/git-repository-async.js

@@ -41,9 +41,9 @@ export default class GitRepositoryAsync {
       this.subscriptions.add(new Disposable(() => window.removeEventListener('focus', onWindowFocus)))
     }
 
-    const {project} = options
+    const {project, subscribeToBuffers} = options
     this.project = project
-    if (this.project) {
+    if (this.project && subscribeToBuffers) {
       this.project.getBuffers().forEach(buffer => this.subscribeToBuffer(buffer))
       this.subscriptions.add(this.project.onDidAddBuffer(buffer => this.subscribeToBuffer(buffer)))
     }

src/git-repository.coffee

@@ -76,7 +76,14 @@ class GitRepository
     unless @repo?
       throw new Error("No Git repository found searching path: #{path}")
 
-    @async = GitRepositoryAsync.open(path, options)
+    asyncOptions = {}
+    for key, val of options
+      asyncOptions[key] = val
+    # GitRepository itself will handle these cases by manually calling through
+    # to the async repo.
+    asyncOptions.refreshOnWindowFocus = false
+    asyncOptions.subscribeToBuffers = false
+    @async = GitRepositoryAsync.open(path, asyncOptions)
 
     @statuses = {}
     @upstream = {ahead: 0, behind: 0}