Media Galleries: Fix render-process-gone case in GetMetadata call

chrome/browser/extensions/api/media_galleries/media_galleries_api.cc

Index: chrome/browser/extensions/api/media_galleries/media_galleries_api.cc
diff --git a/chrome/browser/extensions/api/media_galleries/media_galleries_api.cc b/chrome/browser/extensions/api/media_galleries/media_galleries_api.cc
index 492f8da62a959656cc538b9502ba941d736e4dc5..d5d062629d2eb08ed1e8e26994ff41f5fd5ef733 100644
--- a/chrome/browser/extensions/api/media_galleries/media_galleries_api.cc
+++ b/chrome/browser/extensions/api/media_galleries/media_galleries_api.cc
@@ -752,9 +752,16 @@ void MediaGalleriesGetMetadataFunction::ConstructNextBlob(
   attached_images_list->Append(std::move(attached_image));
 
   blob_uuids->push_back(current_blob->GetUUID());
+
+  content::RenderProcessHost* render_process_host =
+      render_frame_host()->GetProcess();
+  if (!render_process_host) {
+    SendResponse(false);
+    return;
+  }
+
   extensions::BlobHolder* holder =
-      extensions::BlobHolder::FromRenderProcessHost(
-          render_frame_host()->GetProcess());
+      extensions::BlobHolder::FromRenderProcessHost(render_process_host);
   holder->HoldBlobReference(std::move(current_blob));
 
   // Construct the next Blob if necessary.