Fix threading issues in BlacklistManager, using new ChromeThread.

chrome/browser/extensions/extensions_service.cc

Index: chrome/browser/extensions/extensions_service.cc
diff --git a/chrome/browser/extensions/extensions_service.cc b/chrome/browser/extensions/extensions_service.cc
index 2323e6dd94da157ec01a6cdc03ce9f7a056641ba..6103babb7651cb72494ec69e566bdd7c95bb830c 100644
--- a/chrome/browser/extensions/extensions_service.cc
+++ b/chrome/browser/extensions/extensions_service.cc
@@ -742,6 +742,8 @@ void ExtensionsService::ReportExtensionLoadError(
 }
 
 std::vector<FilePath> ExtensionsService::GetPersistentBlacklistPaths() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+
   std::vector<FilePath> result;
   for (ExtensionList::const_iterator extension_iter = extensions()->begin();
        extension_iter != extensions()->end(); ++extension_iter) {
@@ -760,6 +762,8 @@ std::vector<FilePath> ExtensionsService::GetPersistentBlacklistPaths() {
 }
 
 std::vector<FilePath> ExtensionsService::GetTransientBlacklistPaths() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+
   std::vector<FilePath> result;
   for (ExtensionList::const_iterator extension_iter = extensions()->begin();
        extension_iter != extensions()->end(); ++extension_iter) {