[sync] Prevent sessions flare on startup

chrome/browser/sync/sessions/sync_sessions_web_contents_router.cc

 // Copyright 2017 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/sync/sessions/sync_sessions_web_contents_router.h"
 
 #include "chrome/browser/history/history_service_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #if !defined(OS_ANDROID)
 #include "chrome/browser/sync/sessions/browser_list_router_helper.h"
 #else
 #include "chrome/browser/android/tab_android.h"
 #endif  // !defined(OS_ANDROID)
 #include "chrome/browser/ui/sync/tab_contents_synced_tab_delegate.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "components/history/core/browser/history_service.h"
+#include "components/sync_sessions/sync_sessions_client.h"
 #include "components/sync_sessions/synced_tab_delegate.h"
 
 namespace sync_sessions {
 
 namespace {
 
 SyncedTabDelegate* GetSyncedTabDelegateFromWebContents(
     content::WebContents* web_contents) {
 #if defined(OS_ANDROID)
   TabAndroid* tab = TabAndroid::FromWebContents(web_contents);
@@ skipping 18 matching lines @@
   }
 
 #if !defined(OS_ANDROID)
   browser_list_helper_ = base::MakeUnique<BrowserListRouterHelper>(this);
 #endif  // !defined(OS_ANDROID)
 }
 
 SyncSessionsWebContentsRouter::~SyncSessionsWebContentsRouter() {}
 
 void SyncSessionsWebContentsRouter::NotifyTabModified(
-    content::WebContents* web_contents) {
-  if (handler_ && web_contents) {
-    SyncedTabDelegate* delegate =
-        GetSyncedTabDelegateFromWebContents(web_contents);
-    if (delegate)
-      handler_->OnLocalTabModified(delegate);
+    content::WebContents* web_contents,
+    bool page_load_completed) {
+  SyncedTabDelegate* delegate = nullptr;
+  if (web_contents)
+    delegate = GetSyncedTabDelegateFromWebContents(web_contents);
+
+  if (handler_ && delegate) {
+    handler_->OnLocalTabModified(delegate);
   }
 
-  if (!flare_.is_null()) {
+  if (!flare_.is_null() && delegate && page_load_completed) {
     flare_.Run(syncer::SESSIONS);
     flare_.Reset();
   }
 }
 
 void SyncSessionsWebContentsRouter::InjectStartSyncFlare(
     syncer::SyncableService::StartSyncFlare flare) {
   flare_ = flare;
 }
 
@@ skipping 15 matching lines @@
 
 void SyncSessionsWebContentsRouter::Shutdown() {
   favicon_changed_subscription_.reset();
 
 #if !defined(OS_ANDROID)
   browser_list_helper_.reset();
 #endif  // !defined(OS_ANDROID)
 }
 
 }  // namespace sync_sessions