More aggressive IO asserts in content_browsertests.

net/test/test_data_directory.cc

Index: net/test/test_data_directory.cc
diff --git a/net/test/test_data_directory.cc b/net/test/test_data_directory.cc
index aad3d07f243b0da29f1a53a1be8f20af9983f835..b35392407bb2724cdc95d01aedbfa9b71930be6b 100644
--- a/net/test/test_data_directory.cc
+++ b/net/test/test_data_directory.cc
@@ -6,6 +6,7 @@
 
 #include "base/base_paths.h"
 #include "base/path_service.h"
+#include "base/threading/thread_restrictions.h"
 
 namespace net {
 
@@ -16,7 +17,11 @@ const base::FilePath::CharType kCertificateRelativePath[] =
 
 base::FilePath GetTestCertsDirectory() {
   base::FilePath src_root;
-  PathService::Get(base::DIR_SOURCE_ROOT, &src_root);
+  {
+    base::ThreadRestrictions::ScopedAllowIO allow_io_for_path_service;
+    PathService::Get(base::DIR_SOURCE_ROOT, &src_root);
+  }
+
   return src_root.Append(kCertificateRelativePath);
 }