Remove linked_ptr from c/b/media_galleries

Use std::unique_ptr instead of deprecated linked_ptr.

BUG=556939

Change-Id: Icf51f7747b2467afe7ffe3995cd7d4e749b31e11
Reviewed-on: https://chromium-review.googlesource.com/578302
Commit-Queue: Xiaofeng Zhang <xiaofeng.zhang@intel.com>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#488587}

chrome/browser/media_galleries/gallery_watch_manager.cc

@@ -79,8 +79,8 @@ class GalleryWatchManager::FileWatchManager {
   base::WeakPtr<FileWatchManager> GetWeakPtr();
 
  private:
-  typedef std::map<base::FilePath, linked_ptr<base::FilePathWatcher> >
-      WatcherMap;
+  using WatcherMap =
+      std::map<base::FilePath, std::unique_ptr<base::FilePathWatcher>>;
 
   void OnFilePathChanged(const base::FilePath& path, bool error);
 
@@ -116,14 +116,14 @@ void GalleryWatchManager::FileWatchManager::AddFileWatch(
     return;
   }
 
-  linked_ptr<base::FilePathWatcher> watcher(new base::FilePathWatcher);
+  auto watcher = base::MakeUnique<base::FilePathWatcher>();
   bool success = watcher->Watch(path,
                                 true /*recursive*/,
                                 base::Bind(&FileWatchManager::OnFilePathChanged,
                                            weak_factory_.GetWeakPtr()));
 
   if (success)
-    watchers_[path] = watcher;
+    watchers_[path] = std::move(watcher);
 
   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                           base::BindOnce(callback, success));

chrome/browser/media_galleries/gallery_watch_manager.h

@@ -13,7 +13,6 @@
 #include "base/files/file_path.h"
 #include "base/files/file_path_watcher.h"
 #include "base/macros.h"
-#include "base/memory/linked_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "chrome/browser/media_galleries/media_galleries_preferences.h"