Clean up Blink left-overs of textual persistent notification ids.

public/platform/modules/notifications/WebNotificationManager.h

Index: public/platform/modules/notifications/WebNotificationManager.h
diff --git a/public/platform/modules/notifications/WebNotificationManager.h b/public/platform/modules/notifications/WebNotificationManager.h
index d8432293b85b1481226c8efb5f41b05e5174e3f1..110c2bf7d654cac2e62c77e4afe525570c89eaf8 100644
--- a/public/platform/modules/notifications/WebNotificationManager.h
+++ b/public/platform/modules/notifications/WebNotificationManager.h
@@ -6,7 +6,6 @@
 #define WebNotificationManager_h
 
 #include "public/platform/WebCallbacks.h"
-#include "public/platform/WebCommon.h"
 #include "public/platform/WebString.h"
 #include "public/platform/WebVector.h"
 #include "public/platform/modules/notifications/WebNotificationData.h"
@@ -21,9 +20,6 @@ class WebServiceWorkerRegistration;
 
 // Structure representing the info associated with a persistent notification.
 struct WebPersistentNotificationInfo {
-    // TODO(peter): Remove the string property when Chromium has switched over.
-    WebString persistentNotificationId;
-
     int64_t persistentId = 0;
     WebNotificationData data;
 };
@@ -54,16 +50,7 @@ public:
     virtual void close(WebNotificationDelegate*) = 0;
 
     // Closes a persistent notification identified by its persistent notification Id.
-    virtual void closePersistent(const WebSerializedOrigin&, int64_t persistentNotificationId)
-    {
-        BLINK_ASSERT_NOT_REACHED();
-    }
-
-    // TODO(peter): Remove this method when the embedder accepts integral persistent ids.
-    virtual void closePersistent(const WebSerializedOrigin&, const WebString& persistentNotificationId)
-    {
-        BLINK_ASSERT_NOT_REACHED();
-    }
+    virtual void closePersistent(const WebSerializedOrigin&, int64_t persistentNotificationId) = 0;
 
     // Indicates that the delegate object is being destroyed, and must no longer
     // be used by the embedder to dispatch events.