[1/3 blink] Support redirect option of Request and "opaqueredirect" response type.

Source/modules/fetch/Request.idl

Index: Source/modules/fetch/Request.idl
diff --git a/Source/modules/fetch/Request.idl b/Source/modules/fetch/Request.idl
index 1f7deb46590c1e6682847e09144d8e13a7754174..7d226aa3b03616bd408a25cf3a4f5f4c12b5198a 100644
--- a/Source/modules/fetch/Request.idl
+++ b/Source/modules/fetch/Request.idl
@@ -15,6 +15,8 @@ enum RequestContext {
 };
 enum RequestMode { "same-origin", "no-cors", "cors" };
 enum RequestCredentials { "omit", "same-origin", "include" };
+// TODO(horo): Support RequestRedirect when the chromium side patch land.
+// enum RequestRedirect { "follow", "error", "manual" };
 
 [
     Constructor(RequestInfo input, optional Dictionary requestInitDict),
@@ -32,6 +34,8 @@ enum RequestCredentials { "omit", "same-origin", "include" };
     readonly attribute DOMString referrer;
     readonly attribute RequestMode mode;
     readonly attribute RequestCredentials credentials;
+    // TODO(horo): Support redirect attribute when the chromium side patch land.
+    // readonly attribute RequestRedirect redirect;
 
     [RaisesException] Request clone();
 };