Histogram the scheme of an origin on the 1st navigation to it.

chrome/browser/tab_contents/origins_seen_service_factory.cc

Index: chrome/browser/tab_contents/origins_seen_service_factory.cc
diff --git a/chrome/browser/tab_contents/origins_seen_service_factory.cc b/chrome/browser/tab_contents/origins_seen_service_factory.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3a270c72b740700e0759a8a4f0a92e95ae426681
--- /dev/null
+++ b/chrome/browser/tab_contents/origins_seen_service_factory.cc
@@ -0,0 +1,39 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/tab_contents/origins_seen_service_factory.h"
+
+#include "chrome/browser/profiles/incognito_helpers.h"

[Avi (use Gerrit), 2016/04/14 19:08:02]

Do you need this?

[palmer, 2016/04/14 20:13:41]

Done.

+#include "chrome/browser/profiles/profile.h"

[Avi (use Gerrit), 2016/04/14 19:08:02]

You don't need this line...

[palmer, 2016/04/14 20:13:41]

Done.

+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+
+// static
+OriginsSeenService* OriginsSeenServiceFactory::GetForBrowserContext(
+    content::BrowserContext* context) {
+  return static_cast<OriginsSeenService*>(
+      GetInstance()->GetServiceForBrowserContext(context, true));
+}
+
+// static
+OriginsSeenServiceFactory* OriginsSeenServiceFactory::GetInstance() {
+  return base::Singleton<OriginsSeenServiceFactory>::get();
+}
+
+// static
+KeyedService* OriginsSeenServiceFactory::BuildInstanceFor(
+    content::BrowserContext* context) {
+  return new OriginsSeenService();
+}
+
+OriginsSeenServiceFactory::OriginsSeenServiceFactory()
+    : BrowserContextKeyedServiceFactory(
+          "OriginsSeenService",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+OriginsSeenServiceFactory::~OriginsSeenServiceFactory() {}
+
+KeyedService* OriginsSeenServiceFactory::BuildServiceInstanceFor(
+    content::BrowserContext* profile) const {

[Avi (use Gerrit), 2016/04/14 19:08:02]

|context|, not |profile|.

[palmer, 2016/04/14 20:13:41]

Done.

+  return BuildInstanceFor(static_cast<Profile*>(profile));

[Avi (use Gerrit), 2016/04/14 19:08:02]

... because you don't need this cast, as BuildInstanceFor takes a
BrowserContext.

[palmer, 2016/04/14 20:13:41]

Done.

+}