UserAgent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 YaBrowser/16.9.1.1192 Safari/537.36

Steps to reproduce the problem:
In ExtensionSystemImpl::Shared::Init ContentVerifier and SharedUserScriptMaster
instances are initialized in the following way:
 - create ContentVerifier
 - create SharedUserScriptMaster (SharedUserScriptMaster subscribes to
   ExtensionRegistry notifications in constructor)
 - start ContentVerifier (ContentVerifier subscribes to ExtensionRegistry
   notifications in ContentVerifier::Start)

Therefore SharedUserScriptMaster instance gets OnExtensionLoaded
notifications before ContentVerifier instance does.

ContentVerifier starts the following call sequence in OnExtensionLoaded method:
 - ContentVerifier::OnExtensionLoaded (UI)
 - ContentVerifier::AddOrReplaceIOData (IO)

SharedUserScriptMaster starts the following call sequence in OnExtensionLoaded
method:
 - SharedScriptUserMaster::OnExtensionLoaded (UI)
 - UserScriptLoader::AddScripts (UI)
 - UserScriptLoader::AttemptLoad (UI)
 - UserScriptLoader::StartLoad (UI)
 - ExtensionUserScriptLoader::LoadScripts (UI)
 - LoadScriptsOnFileThread (FILE)
 - LoadUserScripts (FILE)
 - LoadScriptContent (FILE)
 - VerifyContent (IO)
 - ContentVerifier::CreateJobFor (IO)

ContentVerifier::AddOrReplaceIOData and ContentVerifier::CreateJobFor try
to create/access the same io_data_ element.
As long as SharedScriptUserMaster gets OnExtensionLoaded notification
first, the threads can be scheduled in the way that VerifyContent task will
get posted on IO thread before ContentVerifier::AddOrReplaceIOData task.
(UI thread should be interrupted before call to
ContentVerifier::OnExtensionLoaded, and FILE thread should be run up to
adding VerifyContent task to IO thread)
After that ContentVerifier::CreateJobFor will fail to get
ContentVerifierIOData from io_data_ and exit after if (!data) check.

What is the expected behavior?

What went wrong?

Did this work before? N/A 

Chrome version: 52.0.2743.116  Channel: n/a
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: Shockwave Flash 23.0 r0