Enable sync by default on all platforms.

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index d380578b38aacf614a40a6c43fad964a256995d0..ca95b979fb9840753e10cd27539ab1777df7889e 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -425,11 +425,9 @@ void ProfileSyncService::SyncEvent(SyncEventCodes code) {
 }
 
 bool ProfileSyncService::IsSyncEnabled() {
-#if defined(OS_POSIX)
-  return CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableSync);
-#else
+  // We have switches::kEnableSync just in case we need to change back to
+  // sync-disabled-by-default on a platform.
   return !CommandLine::ForCurrentProcess()->HasSwitch(switches::kDisableSync);
-#endif
 }
 
 bool ProfileSyncService::ShouldPushChanges() {