Loosen permission on extension temp dir when a flag is used.

base/file_util_posix.cc

Index: base/file_util_posix.cc
diff --git a/base/file_util_posix.cc b/base/file_util_posix.cc
index 9d738da0f121703c8052b18e7c908f4fa8152099..434c859f945769c75b9c73bafca836ae3131b1de 100644
--- a/base/file_util_posix.cc
+++ b/base/file_util_posix.cc
@@ -428,7 +428,15 @@ static bool CreateTemporaryDirInDirImpl(const FilePath& base_dir,
 
 bool CreateTemporaryDirInDir(const FilePath& base_dir,
                              const FilePath::StringType& prefix,
+                             bool loosen_permissions,
                              FilePath* new_dir) {
+  // To understand crbug/35198, the ability to call this
+  // this function on windows while giving loose permissions
+  // to the resulting directory has been temporarily added.
+  // It should not be possible to call this function with
+  // loosen_permissions == true on non-windows platforms.
+  DCHECK(!loosen_permissions);
+
   FilePath::StringType mkdtemp_template = prefix;
   mkdtemp_template.append(FILE_PATH_LITERAL("XXXXXX"));
   return CreateTemporaryDirInDirImpl(base_dir, mkdtemp_template, new_dir);