[Sync] Fix namespaces for the sync_sessions component.

ios/public/provider/chrome/browser/chrome_browser_provider.h

Index: ios/public/provider/chrome/browser/chrome_browser_provider.h
diff --git a/ios/public/provider/chrome/browser/chrome_browser_provider.h b/ios/public/provider/chrome/browser/chrome_browser_provider.h
index 4b11a5502daf0fb008cbc7fdc041d0daa1b9a304..d4a574fc3de60ec6cd86b3e8d0424824ae37e8c4 100644
--- a/ios/public/provider/chrome/browser/chrome_browser_provider.h
+++ b/ios/public/provider/chrome/browser/chrome_browser_provider.h
@@ -28,14 +28,14 @@ class CardUnmaskPromptController;
 class CardUnmaskPromptView;
 }
 
-namespace browser_sync {
-class SyncedWindowDelegatesGetter;
-}
-
 namespace net {
 class URLRequestContextGetter;
 }
 
+namespace sync_sessions {
+class SyncedWindowDelegatesGetter;
+}
+
 namespace user_prefs {
 class PrefRegistrySyncable;
 }
@@ -115,7 +115,7 @@ class ChromeBrowserProvider {
   virtual bool IsSafeBrowsingEnabled(const base::Closure& on_update_callback);
 
   // Returns the SyncedWindowDelegatesGetter implementation.
-  virtual std::unique_ptr<browser_sync::SyncedWindowDelegatesGetter>
+  virtual std::unique_ptr<sync_sessions::SyncedWindowDelegatesGetter>
   CreateSyncedWindowDelegatesGetter(ios::ChromeBrowserState* browser_state);
 };