Remove variable shadowing in blink/modules/notifications

In an effort to reduce or even ban variable shadowing, this renames
a variable to avoid such shadowing. I'm interested in prohibiting
shadowing because I think it might prevent potential jumbo problems.

The exact error this avoids is:
third_party/blink/renderer/modules/notifications/notification_data.cc:93:45: error: declaration shadows a local variable [-Werror,-Wshadow]

    SerializedScriptValue::SerializeOptions options;
                                            ^
./../../third_party/blink/renderer/modules/notifications/notification_data.cc:43:32: note: previous declaration is here
    const NotificationOptions* options,
                               ^

Bug: 923510
Change-Id: Ie49096ef30fbab30567ad45f3f2d8b76a8eab9ed
Reviewed-on: https://chromium-review.googlesource.com/c/1478891Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#633744}

third_party/blink/renderer/modules/notifications/notification_data.cc

@@ -90,11 +90,11 @@ mojom::blink::NotificationDataPtr CreateNotificationData(
     const ScriptValue& data = options->data();
     v8::Isolate* isolate = data.GetIsolate();
     DCHECK(isolate->InContext());
-    SerializedScriptValue::SerializeOptions options;
-    options.for_storage = SerializedScriptValue::kForStorage;
+    SerializedScriptValue::SerializeOptions serialize_options;
+    serialize_options.for_storage = SerializedScriptValue::kForStorage;
     scoped_refptr<SerializedScriptValue> serialized_script_value =
-        SerializedScriptValue::Serialize(isolate, data.V8Value(), options,
-                                         exception_state);
+        SerializedScriptValue::Serialize(isolate, data.V8Value(),
+                                         serialize_options, exception_state);
     if (exception_state.HadException())
       return nullptr;