Use SyncMessageFilter to Send() ipc messages from background threads.

content/common/web_database_observer_impl.cc

Index: content/common/web_database_observer_impl.cc
===================================================================
--- content/common/web_database_observer_impl.cc	(revision 124748)
+++ content/common/web_database_observer_impl.cc	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -11,6 +11,8 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDatabase.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebString.h"
 
+#include "base/rand_util.h"
+
 using WebKit::WebDatabase;
 
 namespace {
@@ -61,7 +63,7 @@
 }  // namespace
 
 WebDatabaseObserverImpl::WebDatabaseObserverImpl(
-    IPC::Message::Sender* sender)
+    IPC::SyncMessageFilter* sender)
     : sender_(sender),
       open_connections_(new webkit_database::DatabaseConnectionsWrapper) {
 }
@@ -153,6 +155,12 @@
 
 void WebDatabaseObserverImpl::HandleSqliteError(
     const WebDatabase& database, int error) {
+  // JUNK TO INDUCE ERRORS
+  int rand = base::RandInt(0, 10000);
+  if (rand < 5)
+    error = SQLITE_CORRUPT;
+  // JUNK TO INDUCE ERRORS

[michaeln, 2012/03/06 00:39:18]

oh... nevermind this JUNK and the base/rand_util include, it's unrelated and not
part of the intended CL  (this should screw up my tryjobs pretty good:)

+
   // We filter out errors which the backend doesn't act on to avoid
   // a unnecessary ipc traffic, this method can get called at a fairly
   // high frequency (per-sqlstatement).