Take 2 at browser_sync::ExtensionsActivityMonitor....

chrome/browser/sync/engine/build_commit_command.cc

 // Copyright (c) 2006-2009 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 "chrome/browser/sync/engine/build_commit_command.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
@@ skipping 12 matching lines @@
 using syncable::ExtendedAttribute;
 using syncable::Id;
 using syncable::MutableEntry;
 using syncable::Name;
 
 namespace browser_sync {
 
 BuildCommitCommand::BuildCommitCommand() {}
 BuildCommitCommand::~BuildCommitCommand() {}
 
+void BuildCommitCommand::AddExtensionsActivityToMessage(
+    SyncerSession* session, CommitMessage* message) {
+  const ExtensionsActivityMonitor::Records& records =
+      session->extensions_activity();
+  for (ExtensionsActivityMonitor::Records::const_iterator it = records.begin();
+       it != records.end(); ++it) {
+    sync_pb::CommitMessage_ChromiumExtensionsActivity* activity_message =
+        message->add_extensions_activity();
+    activity_message->set_extension_id(it->second.extension_id);
+    activity_message->set_bookmark_writes_since_last_commit(
+        it->second.bookmark_write_count);
+  }
+}
+
 void BuildCommitCommand::ExecuteImpl(SyncerSession* session) {
   ClientToServerMessage message;
   message.set_share(ToUTF8(session->account_name()).get_string());
   message.set_message_contents(ClientToServerMessage::COMMIT);
 
   CommitMessage* commit_message = message.mutable_commit();
   commit_message->set_cache_guid(
       session->write_transaction()->directory()->cache_guid());
+  AddExtensionsActivityToMessage(session, commit_message);
 
   const vector<Id>& commit_ids = session->commit_ids();
   for (size_t i = 0; i < commit_ids.size(); i++) {
     Id id = commit_ids[i];
     SyncEntity* sync_entry =
         static_cast<SyncEntity*>(commit_message->add_entries());
     sync_entry->set_id(id);
     MutableEntry meta_entry(session->write_transaction(),
                             syncable::GET_BY_ID,
                             id);
@@ skipping 82 matching lines @@
         SyncerProtoUtil::CopyBlobIntoProtoBytes(
             meta_entry.Get(syncable::BOOKMARK_FAVICON),
             bookmark->mutable_bookmark_favicon());
       }
     }
   }
   session->set_commit_message(message);
 }
 
 }  // namespace browser_sync