Wait for the DB thread to finish posting tasks to the main thread
before setting the WebKit client to NULL.

TEST=none
BUG=32228,32226

Review URL: http://codereview.chromium.org/545178

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@37594 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/renderer/render_thread.cc b/chrome/renderer/render_thread.cc
index 1b4cd96..2d47a43d 100644
--- a/chrome/renderer/render_thread.cc
+++ b/chrome/renderer/render_thread.cc
@@ -210,10 +210,15 @@
 }
 
 RenderThread::~RenderThread() {
+  // Wait for all databases to be closed.
+  if (renderer_web_database_observer_.get())
+    renderer_web_database_observer_->WaitForAllDatabasesToClose();
+
   // Shutdown in reverse of the initialization order.
   RemoveFilter(devtools_agent_filter_.get());
   RemoveFilter(db_message_filter_.get());
   db_message_filter_ = NULL;
+
   if (webkit_client_.get())
     WebKit::shutdown();