Refactor getInstalledRelatedApps code and add manifest logic and tests.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index e7d049c0d22cfd26f8f3ce455df2af10182aee9a..db9b429808bf0c1da98b692f4b288891f203a562 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -106,6 +106,7 @@
 #include "content/renderer/image_downloader/image_downloader_impl.h"
 #include "content/renderer/ime_event_guard.h"
 #include "content/renderer/input/input_handler_manager.h"
+#include "content/renderer/installedapp/related_apps_fetcher.h"
 #include "content/renderer/internal_document_state_data.h"
 #include "content/renderer/manifest/manifest_manager.h"
 #include "content/renderer/media/audio_device_factory.h"
@@ -4566,6 +4567,13 @@ blink::WebPushClient* RenderFrameImpl::pushClient() {
   return push_messaging_dispatcher_;
 }
 
+blink::WebRelatedAppsFetcher* RenderFrameImpl::relatedAppsFetcher() {
+  if (!related_apps_fetcher_)
+    related_apps_fetcher_.reset(new RelatedAppsFetcher(manifest_manager_));
+
+  return related_apps_fetcher_.get();
+}
+
 void RenderFrameImpl::willStartUsingPeerConnectionHandler(
     blink::WebRTCPeerConnectionHandler* handler) {
 #if BUILDFLAG(ENABLE_WEBRTC)