IndexedDB: Don't timeout read-only transactions

content/browser/indexed_db/indexed_db_transaction.cc

 // Copyright (c) 2013 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 "content/browser/indexed_db/indexed_db_transaction.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 300 matching lines @@
   if (!HasPendingTasks() && state_ != FINISHED && commit_pending_) {
     Commit();
     return;
   }
 
   // The transaction may have been aborted while processing tasks.
   if (state_ == FINISHED)
     return;
 
   // Otherwise, start a timer in case the front-end gets wedged and
-  // never requests further activity.
-  timeout_timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromSeconds(kInactivityTimeoutPeriodSeconds),
-      base::Bind(&IndexedDBTransaction::Timeout, this));
+  // never requests further activity. Read-only transactions don't
+  // block other transactions, so don't time those out.
+  if (mode_ != indexed_db::TRANSACTION_READ_ONLY) {
+    timeout_timer_.Start(
+        FROM_HERE,
+        base::TimeDelta::FromSeconds(kInactivityTimeoutPeriodSeconds),
+        base::Bind(&IndexedDBTransaction::Timeout, this));
+  }
 }
 
 void IndexedDBTransaction::Timeout() {
   Abort(IndexedDBDatabaseError(
       blink::WebIDBDatabaseExceptionTimeoutError,
       base::ASCIIToUTF16("Transaction timed out due to inactivity.")));
 }
 
 void IndexedDBTransaction::CloseOpenCursors() {
   for (std::set<IndexedDBCursor*>::iterator i = open_cursors_.begin();
        i != open_cursors_.end();
        ++i)
     (*i)->Close();
   open_cursors_.clear();
 }
 
 }  // namespace content