[Sync] Fix namespaces for the sync_sessions component.

components/sync_sessions/sync_sessions_client.h

Index: components/sync_sessions/sync_sessions_client.h
diff --git a/components/sync_sessions/sync_sessions_client.h b/components/sync_sessions/sync_sessions_client.h
index 9d53cd781aef5da10a859c279d5d6c4e31e1e26a..fab928ffefff195f01f670b101cb9d694efa1941 100644
--- a/components/sync_sessions/sync_sessions_client.h
+++ b/components/sync_sessions/sync_sessions_client.h
@@ -15,11 +15,6 @@ namespace bookmarks {
 class BookmarkModel;
 }
 
-namespace browser_sync {
-class LocalSessionEventRouter;
-class SyncedWindowDelegatesGetter;
-}
-
 namespace favicon {
 class FaviconService;
 }
@@ -30,6 +25,9 @@ class HistoryService;
 
 namespace sync_sessions {
 
+class LocalSessionEventRouter;
+class SyncedWindowDelegatesGetter;
+
 // Interface for clients of a sync sessions datatype. Should be used as a getter
 // for services and data the Sync Sessions datatype depends on.
 class SyncSessionsClient {
@@ -50,12 +48,11 @@ class SyncSessionsClient {
   virtual bool ShouldSyncURL(const GURL& url) const = 0;
 
   // Returns the SyncedWindowDelegatesGetter for this client.
-  virtual browser_sync::SyncedWindowDelegatesGetter*
-  GetSyncedWindowDelegatesGetter() = 0;
+  virtual SyncedWindowDelegatesGetter* GetSyncedWindowDelegatesGetter() = 0;
 
   // Returns a LocalSessionEventRouter instance that is customized for the
   // embedder's context.
-  virtual std::unique_ptr<browser_sync::LocalSessionEventRouter>
+  virtual std::unique_ptr<LocalSessionEventRouter>
   GetLocalSessionEventRouter() = 0;
 
   // TODO(zea): add getters for the history and favicon services for the favicon