[Merge M100] [crash] Never try to initialize SessionService before pr…

…ofile prefs are loaded

Diagnosis @ crbug.com/1300724#c4

(cherry picked from commit e92e082)

Fixed: 1300724
Change-Id: I074f9c63cd2325731612140e53ba0390707b0a57
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3510667
Commit-Queue: Gabriel Charette <gab@chromium.org>
Auto-Submit: Gabriel Charette <gab@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#978864}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3550760
Cr-Commit-Position: refs/branch-heads/4896@{#866}
Cr-Branched-From: 1f63ff4-refs/heads/main@{#972766}

chrome/browser/profiles/profile_impl.cc

@@ -459,12 +459,6 @@ ProfileImpl::ProfileImpl(
   }
 #endif
 
-#if BUILDFLAG(ENABLE_SESSION_SERVICE)
-  create_session_service_timer_.Start(
-      FROM_HERE, kCreateSessionServiceDelay, this,
-      &ProfileImpl::EnsureSessionServiceCreated);
-#endif
-
   if (path == ProfileManager::GetGuestProfilePath()) {
       profile_metrics::SetBrowserProfileType(
           this, profile_metrics::BrowserProfileType::kGuest);
@@ -1148,6 +1142,15 @@ void ProfileImpl::OnPrefsLoaded(CreateMode create_mode, bool success) {
 #else
   OnLocaleReady(create_mode);
 #endif
+
+#if BUILDFLAG(ENABLE_SESSION_SERVICE)
+  // SessionService depends on Profile::GetPrefs() and therefore shouldn't be
+  // forced initialized before prefs are loaded. Starting this Timer before
+  // that point resulted in a racy use-before-initialized in the past.
+  create_session_service_timer_.Start(
+      FROM_HERE, kCreateSessionServiceDelay, this,
+      &ProfileImpl::EnsureSessionServiceCreated);
+#endif
 }
 
 bool ProfileImpl::WasCreatedByVersionOrLater(const std::string& version) {