[Tab Metrics] Measure FP, FCP and FMP for Foreground Tab during Session Restore

chrome/browser/sessions/session_restore.cc

Index: chrome/browser/sessions/session_restore.cc
diff --git a/chrome/browser/sessions/session_restore.cc b/chrome/browser/sessions/session_restore.cc
index db3bc9ddab8a9348e27653a3fe120d85e023bf33..9d5ca3a4dd6b8f914aa9e435be0e5a0af54bece7 100644
--- a/chrome/browser/sessions/session_restore.cc
+++ b/chrome/browser/sessions/session_restore.cc
@@ -91,6 +91,27 @@ std::set<SessionRestoreImpl*>* active_session_restorers = nullptr;
 
 }  // namespace
 
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(RestoreOrigin);
+
+// static
+void RestoreOrigin::CreateForWebContents(content::WebContents* contents,
+                                         RestoreOrigin::Type type) {
+  DCHECK(contents);
+  if (!FromWebContents(contents))
+    contents->SetUserData(UserDataKey(),
+                          base::WrapUnique(new RestoreOrigin(type)));
+}
+
+// static
+void RestoreOrigin::RemoveFromWebContents(content::WebContents* contents) {
+  if (FromWebContents(contents))
+    contents->RemoveUserData(UserDataKey());
+}
+
+RestoreOrigin::RestoreOrigin(RestoreOrigin::Type type) : type_(type) {}
+
+RestoreOrigin::~RestoreOrigin() = default;
+
 // SessionRestoreImpl ---------------------------------------------------------
 
 // SessionRestoreImpl is responsible for fetching the set of tabs to create
@@ -616,7 +637,8 @@ class SessionRestoreImpl : public content::NotificationObserver {
     WebContents* web_contents = chrome::AddRestoredTab(
         browser, tab.navigations, tab_index, selected_index,
         tab.extension_app_id, is_selected_tab, tab.pinned, true,
-        session_storage_namespace.get(), tab.user_agent_override);
+        session_storage_namespace.get(), tab.user_agent_override,
+        RestoreOrigin::Type::SESSION_RESTORE);
     // Regression check: if the current tab |is_selected_tab|, it should load
     // immediately, otherwise, tabs should not start loading right away. The
     // focused tab will be loaded by Browser, and TabLoader will load the rest.