Convert WindowOpenDisposition to an enum class.

chrome/browser/extensions/api/web_navigation/web_navigation_api.cc

Index: chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
index 9e72ecab1c2e14e11b5c99cde71abf8aabef1d1d..c15439bae6a5f3ba61cb5e4f6c807d1dee0754b3 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
@@ -374,12 +374,12 @@ void WebNavigationTabObserver::DidOpenRequestedURL(
 
   // We only send the onCreatedNavigationTarget if we end up creating a new
   // window.
-  if (disposition != SINGLETON_TAB &&
-      disposition != NEW_FOREGROUND_TAB &&
-      disposition != NEW_BACKGROUND_TAB &&
-      disposition != NEW_POPUP &&
-      disposition != NEW_WINDOW &&
-      disposition != OFF_THE_RECORD)
+  if (disposition != WindowOpenDisposition::SINGLETON_TAB &&
+      disposition != WindowOpenDisposition::NEW_FOREGROUND_TAB &&
+      disposition != WindowOpenDisposition::NEW_BACKGROUND_TAB &&
+      disposition != WindowOpenDisposition::NEW_POPUP &&
+      disposition != WindowOpenDisposition::NEW_WINDOW &&
+      disposition != WindowOpenDisposition::OFF_THE_RECORD)
     return;
 
   helpers::DispatchOnCreatedNavigationTarget(web_contents(),