[Cast, Android, Presentation API] Fix the logic for showing controller vs chooser dialog

chrome/browser/media/android/router/media_router_android.cc

Index: chrome/browser/media/android/router/media_router_android.cc
diff --git a/chrome/browser/media/android/router/media_router_android.cc b/chrome/browser/media/android/router/media_router_android.cc
index 02fcfb789bdee02d36de701f4997a703069b4c58..ea727d9df3579b063ee4f34e75650dc0f86a2da5 100644
--- a/chrome/browser/media/android/router/media_router_android.cc
+++ b/chrome/browser/media/android/router/media_router_android.cc
@@ -54,6 +54,15 @@ bool MediaRouterAndroid::Register(JNIEnv* env) {
   return ret;
 }
 
+const MediaRoute* MediaRouterAndroid::FindRouteBySource(
+    const MediaSource::Id& source_id) const {
+  for (const auto& route : active_routes_) {
+    if (route.media_source().id() == source_id)
+      return &route;
+  }
+  return nullptr;
+}
+
 void MediaRouterAndroid::CreateRoute(
     const MediaSource::Id& source_id,
     const MediaSink::Id& sink_id,