Remove separate profile logic

When a user is not logged in, ProfileManager::GetPrimaryUserProfile()
returns an off-the-record profile. Instead of defining our own logic
when a user is not logged in, use the existing logic of the function.

BUG=chromium:956783
TEST=none

Change-Id: I66efde824df0c4b5a22d1f1abdb293ddbea011fc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2436510
Commit-Queue: Kartik Hegde <khegde@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812458}

chrome/browser/chromeos/net/network_diagnostics/network_diagnostics_util.cc

@@ -10,9 +10,7 @@
 
 #include "base/no_destructor.h"
 #include "base/rand_util.h"
-#include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile_manager.h"
-#include "components/session_manager/core/session_manager.h"
 #include "content/public/browser/storage_partition.h"
 
 namespace chromeos {
@@ -79,11 +77,6 @@ std::vector<std::string> GetRandomHostsWithFixedHosts(int num_random_hosts,
 }
 
 Profile* GetUserProfile() {
-  // Use sign-in profile if user has not logged in
-  if (session_manager::SessionManager::Get()->IsUserSessionBlocked()) {
-    return ProfileHelper::GetSigninProfile();
-  }
-  // Use primary profile if user is logged in
   return ProfileManager::GetPrimaryUserProfile();
 }