Increase page size for SyncData DB from 4K to maximum supported 32K

sync/syncable/deferred_on_disk_directory_backing_store.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sync/syncable/deferred_on_disk_directory_backing_store.h"
 
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "sync/syncable/syncable-inl.h"
@@ skipping 21 matching lines @@
     return true;
   }
 
   if (!db_is_on_disk_) {
     if (!base::DeleteFile(backing_filepath_, false))
       return false;
 
     // Reopen DB on disk.
     db_.reset(new sql::Connection);
     db_->set_exclusive_locking();
-    db_->set_page_size(4096);
+    if (IsSyncBackingDatabase32KEnabled()) {
+      db_->set_page_size(32768);
+    } else {
+      db_->set_page_size(4096);
+    }
     if (!db_->Open(backing_filepath_) || !InitializeTables())
       return false;
 
     db_is_on_disk_ = true;
   }
 
   return DirectoryBackingStore::SaveChanges(snapshot);
 }
 
 DirOpenResult DeferredOnDiskDirectoryBackingStore::Load(
@@ skipping 11 matching lines @@
   if (!LoadEntries(handles_map))
     return FAILED_DATABASE_CORRUPT;
   if (!LoadInfo(kernel_load_info))
     return FAILED_DATABASE_CORRUPT;
 
   return OPENED;
 }
 
 }  // namespace syncable
 }  // namespace syncer