Check Extension in extension_error_ui_util

chrome/browser/ui/webui/extensions/extension_error_ui_util.cc

Index: chrome/browser/ui/webui/extensions/extension_error_ui_util.cc
diff --git a/chrome/browser/ui/webui/extensions/extension_error_ui_util.cc b/chrome/browser/ui/webui/extensions/extension_error_ui_util.cc
index fc6b728475b0290f6790f81a83d1f7a8a3611f5c..08e8d6f77f9f49570a6f563345250de2dcd58c4f 100644
--- a/chrome/browser/ui/webui/extensions/extension_error_ui_util.cc
+++ b/chrome/browser/ui/webui/extensions/extension_error_ui_util.cc
@@ -15,7 +15,6 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/devtools/devtools_window.h"
-#include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_finder.h"
@@ -24,7 +23,7 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/browser/extension_error.h"
-#include "extensions/browser/extension_system.h"
+#include "extensions/browser/extension_registry.h"
 #include "extensions/browser/file_highlighter.h"
 #include "extensions/common/constants.h"
 #include "extensions/common/extension.h"
@@ -80,13 +79,12 @@ void HandleRequestFileSource(const base::DictionaryValue* args,
     return;
   }
 
-  ExtensionService* extension_service =
-      ExtensionSystem::Get(profile)->extension_service();
-  if (!extension_service)
-    return;
+  const Extension* extension =
+      ExtensionRegistry::Get(profile)->GetExtensionById(
+          extension_id, ExtensionRegistry::EVERYTHING);
 
-  const Extension* extension = extension_service->GetExtensionById(
-      extension_id, true /* include disabled */);
+  if (!extension)
+    return;

[Finnur, 2014/04/10 12:24:02]

Looks like it would fix the crash, but do we have a good understanding as to why
we end up in this situation?  

[Devlin, 2014/04/10 16:21:08]

My suspicion is that, since we really only enter this code path when an
extension encounters an error, the extension may have crashed, and entered the
terminated state (which is the only state which
ExtensionService::GetExtensionById() doesn't check).  I think that subbing in
ExtensionRegistry::GetExtensionById(EVERYTHING) will solve this, but, on the
off-chance it doesn't, we should fail gracefully (at least in release builds). 
Added a NOTREACHED() so we can tell in Debug builds if this truly fixed the
problem.

 
   // Under no circumstances should we ever need to reference a file outside of
   // the extension's directory. If it tries to, abort.