Add WriteIsolatedOutput() functions

webrtc/base/file.cc

Index: webrtc/base/file.cc
diff --git a/webrtc/base/file.cc b/webrtc/base/file.cc
index 8b5df9e9be4f74ae31cac62ff80aa340323bfad5..983eb8b8da673fdb849b87c0782dcaa9d67e6f36 100644
--- a/webrtc/base/file.cc
+++ b/webrtc/base/file.cc
@@ -61,6 +61,21 @@ File File::Create(const Pathname& path) {
   return Create(Pathname(path));
 }
 
+// static
+bool File::Remove(const std::string& path) {
+  return RemoveFile(path);
+}
+
+// static
+bool File::Remove(Pathname&& path) {
+  return Remove(NormalizePathname(std::move(path)));
+}
+
+// static
+bool File::Remove(const Pathname& path) {
+  return Remove(Pathname(path));
+}
+
 File::File(File&& other) : file_(other.file_) {
   other.file_ = kInvalidPlatformFileValue;
 }