Unpack extensions inside chrome's directory.

base/scoped_temp_dir.h

Index: base/scoped_temp_dir.h
diff --git a/base/scoped_temp_dir.h b/base/scoped_temp_dir.h
index e9d45b9a99cfcdc673df70e96d0690ac750ebff8..a5dca1e01a04d4eb68bbe5927a4a6ca73a5de89b 100644
--- a/base/scoped_temp_dir.h
+++ b/base/scoped_temp_dir.h
@@ -25,6 +25,9 @@ class ScopedTempDir {
   // See file_util::CreateNewTemporaryDirectory.
   bool CreateUniqueTempDir();
 
+  // Creates a unique directory under a given path, and takes ownership of it.
+  bool CreateUniqueTempDirUnderPath(const FilePath& path);
+
   // Takes ownership of directory at |path|, creating it if necessary.
   // Don't call multiple times unless Take() has been called first.
   bool Set(const FilePath& path);