service worker: Show clients in the internal page

To investigate invalid states where a redundant service worker
is controlling clients.

DevTools' application tab shows clients nicely but it doesn't
show redundant service workers.

Bug: 1015692
Change-Id: I6102f5d897e8e91a49d8502d8876cac809a2c181
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1890516Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712371}

content/browser/resources/service_worker/serviceworker_internals.css

@@ -35,6 +35,11 @@
     padding-left: 10px;
 }
 
+.serviceworker-client {
+    padding-bottom: 3px;
+    padding-left: 10px;
+}
+
 .controls a {
     -webkit-margin-end: 16px;
     color: #777;

content/browser/resources/service_worker/serviceworker_internals.html

@@ -43,6 +43,10 @@
         <span>DevTools agent route ID:</span>
         <span jscontent="$this.devtools_agent_route_id"></span>
       </div>
+      <div class="serviceworker-clients" jsselect="$this.clients">
+        <div>Client: </div>
+        <div transclude="serviceworker-client-template"></div>
+      </div>
       <div>
         <div>Log:</div>
         <textarea class="serviceworker-log"
@@ -135,7 +139,15 @@
         </label>
       </div>
     </div>
-  </div>
+    <div id="serviceworker-client-template" class="serviceworker-client">
+      <div>
+        <span>ID: </span><span jscontent="$this.client_id"></span>
+      </div>
+      <div>
+        <span>URL: </span><span jscontent="$this.url"></span>
+      </div>
+    </div>
+  </div> <!-- templates end -->
   <h1>ServiceWorker</h1>
   <div class="content">
     <div id="serviceworker-options"></div>

content/browser/service_worker/service_worker_internals_ui.cc

@@ -153,6 +153,19 @@ void UpdateVersionInfo(const ServiceWorkerVersionInfo& version,
   info->SetInteger("process_host_id", version.process_id);
   info->SetInteger("thread_id", version.thread_id);
   info->SetInteger("devtools_agent_route_id", version.devtools_agent_route_id);
+
+  auto clients = ListValue();
+  for (auto& it : version.clients) {
+    auto client = DictionaryValue();
+    client.SetStringPath("client_id", it.first);
+    if (it.second.web_contents_getter) {
+      WebContents* web_contents = it.second.web_contents_getter.Run();
+      if (web_contents)
+        client.SetStringPath("url", web_contents->GetURL().spec());
+    }
+    clients.Append(std::move(client));
+  }
+  info->SetPath("clients", std::move(clients));
 }
 
 std::unique_ptr<ListValue> GetRegistrationListValue(