Thread IO safety: file_util annotated, IO thread blocked from doing IO

chrome/common/extensions/extension_resource.cc

 // Copyright (c) 2010 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.
 
 #include "chrome/common/extensions/extension_resource.h"
 
 #include "base/file_util.h"
 #include "base/logging.h"
+#include "base/thread_restrictions.h"
 
 PlatformThreadId ExtensionResource::file_thread_id_ = 0;
 
 bool ExtensionResource::check_for_file_thread_ = false;
 
 ExtensionResource::ExtensionResource() {
 }
 
 ExtensionResource::ExtensionResource(const std::string& extension_id,
                                      const FilePath& extension_root,
@@ skipping 19 matching lines @@
 }
 
 const FilePath& ExtensionResource::GetFilePath() const {
   ExtensionResource::CheckFileAccessFromFileThread();
   return GetFilePathOnAnyThreadHack();
 }
 
 // static
 FilePath ExtensionResource::GetFilePathOnAnyThreadHack(
     const FilePath& extension_root, const FilePath& relative_path) {
+  // This function is a hack, and causes us to block the IO thread.
+  // Fixing
+  //   http://code.google.com/p/chromium/issues/detail?id=59849
+  // would also fix this.  Suppress the error for now.
+  base::ThreadRestrictions::ScopedAllowIO allow_io;
+
   // We need to resolve the parent references in the extension_root
   // path on its own because IsParent doesn't like parent references.
   FilePath clean_extension_root(extension_root);
   if (!file_util::AbsolutePath(&clean_extension_root))
     return FilePath();
 
   FilePath full_path = clean_extension_root.Append(relative_path);
 
   // We must resolve the absolute path of the combined path when
   // the relative path contains references to a parent folder (i.e., '..').
@@ skipping 41 matching lines @@
   // Make sure we have a cached value to test against...
   if (full_resource_path_.empty())
     GetFilePath();
   if (NormalizeSeperators(path.value()) ==
     NormalizeSeperators(full_resource_path_.value())) {
     return true;
   } else {
     return false;
   }
 }