FIX: Do not raise if title cannot be crawled (#16247)

If the crawled page returned an error, `FinalDestination#safe_get`
yielded `nil` for `uri` and `chunk` arguments. Another problem is that
`get` did not handle the case when `safe_get` failed and did not return
the `location` and `set_cookie` headers.

spec/lib/retrieve_title_spec.rb

@@ -136,6 +136,12 @@ describe RetrieveTitle do
 
       expect(RetrieveTitle.crawl("https://cat.com/meow/no-onebox")).to be_blank
     end
+
+    it "doesn't return a title if response is unsuccessful" do
+      stub_request(:get, "https://example.com").to_return(status: 404, body: "")
+
+      expect(RetrieveTitle.crawl("https://example.com")).to eq(nil)
+    end
   end
 
   context 'fetch_title' do