Remove duplicate init of WebStateListMetricsBrowser

Duplicate initialization was introduced by crrev.com/c/2167852
resulting in a dependency issue.

Previous fix crrev.com/c/2435344
fixed the dependency but kept the double initialization.

Restore the init order pre- crrev.com/c/2167852

Bug: 1132784
Change-Id: I69abeea6826e3aecbad7b321cdda33b6138628de
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2438427Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Olivier Robin <olivierrobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812033}

ios/chrome/browser/main/browser_agent_util.mm

@@ -43,12 +43,6 @@ void AttachBrowserAgents(Browser* browser) {
   UrlLoadingNotifierBrowserAgent::CreateForBrowser(browser);
   AppLauncherBrowserAgent::CreateForBrowser(browser);
 
-  // SessionRestorartionAgent requires WebUsageEnablerBrowserAgent.
-  SessionRestorationBrowserAgent::CreateForBrowser(
-      browser, [SessionServiceIOS sharedService]);
-
-  // WebStateListMetricsBrowserAgent requires SessionRestorationBrowserAgent.
-  WebStateListMetricsBrowserAgent::CreateForBrowser(browser);
   ClosingWebStateObserverBrowserAgent::CreateForBrowser(browser);
   SnapshotBrowserAgent::CreateForBrowser(browser);
 
@@ -59,6 +53,10 @@ void AttachBrowserAgents(Browser* browser) {
   // UrlLoadingBrowserAgent requires UrlLoadingNotifierBrowserAgent.
   UrlLoadingBrowserAgent::CreateForBrowser(browser);
 
+  // SessionRestorartionAgent requires WebUsageEnablerBrowserAgent.
+  SessionRestorationBrowserAgent::CreateForBrowser(
+      browser, [SessionServiceIOS sharedService]);
+
   // TabUsageRecorderBrowserAgent and WebStateListMetricsBrowserAgent observe
   // the SessionRestorationBrowserAgent, so they should be created after the the
   // SessionRestorationBrowserAgent is created.