[Sync] Fix namespaces for the sync_sessions component.

ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm

Index: ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm
diff --git a/ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm b/ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm
index 39f20a9e6ceb95a88d18a57cadeaf9412c62656e..ecab4d09ebd8838bdaa40d58b3def8dc827f7d3f 100644
--- a/ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm
+++ b/ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.mm
@@ -19,9 +19,9 @@
 
 namespace {
 
-browser_sync::SyncedTabDelegate* GetSyncedTabDelegateFromWebState(
+sync_sessions::SyncedTabDelegate* GetSyncedTabDelegateFromWebState(
     web::WebState* web_state) {
-  browser_sync::SyncedTabDelegate* delegate =
+  sync_sessions::SyncedTabDelegate* delegate =
       IOSChromeSyncedTabDelegate::FromWebState(web_state);
   return delegate;
 }
@@ -89,7 +89,7 @@ void IOSChromeLocalSessionEventRouter::OnWebStateChange(
     web::WebState* web_state) {
   if (web_state->GetBrowserState() != browser_state_)
     return;
-  browser_sync::SyncedTabDelegate* tab =
+  sync_sessions::SyncedTabDelegate* tab =
       GetSyncedTabDelegateFromWebState(web_state);
   if (!tab)
     return;
@@ -112,7 +112,7 @@ void IOSChromeLocalSessionEventRouter::OnFaviconsChanged(
 }
 
 void IOSChromeLocalSessionEventRouter::StartRoutingTo(
-    browser_sync::LocalSessionEventHandler* handler) {
+    sync_sessions::LocalSessionEventHandler* handler) {
   DCHECK(!handler_);
   handler_ = handler;
 }