Scope the WriteTransactions during model association so that we don't lock the UI thread

chrome/browser/sync/glue/typed_url_change_processor.cc

Index: chrome/browser/sync/glue/typed_url_change_processor.cc
diff --git a/chrome/browser/sync/glue/typed_url_change_processor.cc b/chrome/browser/sync/glue/typed_url_change_processor.cc
index 709c5e6803bc1f4c4f4d529930cc389db3221e73..4701b3aa2370c2c2cbc7eb8ef8f78451a868729b 100644
--- a/chrome/browser/sync/glue/typed_url_change_processor.cc
+++ b/chrome/browser/sync/glue/typed_url_change_processor.cc
@@ -62,6 +62,9 @@ void TypedUrlChangeProcessor::HandleURLsModified(
     history::URLsModifiedDetails* details) {
   sync_api::WriteTransaction trans(share_handle());
 
+  // TODO(sync): Get visits without holding the write transaction.
+  // See issue 34206
+
   sync_api::ReadNode typed_url_root(&trans);
   if (!typed_url_root.InitByTagLookup(kTypedUrlTag)) {
     error_handler()->OnUnrecoverableError();