Tab Search: Fix TabSearchPageHandler sending extra TabsChanged() on start

Bug: 1099917
Change-Id: I7aeaf8c2f62f36576f418239531ae9c938f305cc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2433589Reviewed-by: Thomas Lukaszewicz <tluk@chromium.org>
Commit-Queue: Yuheng Huang <yuhengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811084}

chrome/browser/ui/webui/tab_search/tab_search_page_handler.cc

@@ -206,7 +206,8 @@ void TabSearchPageHandler::OnTabStripModelChanged(
     TabStripModel* tab_strip_model,
     const TabStripModelChange& change,
     const TabStripSelectionChange& selection) {
-  ScheduleDebounce();
+  if (!browser_tab_strip_tracker_.is_processing_initial_browsers())
+    ScheduleDebounce();
 }
 
 void TabSearchPageHandler::TabChangedAt(content::WebContents* contents,
@@ -229,8 +230,7 @@ void TabSearchPageHandler::ScheduleDebounce() {
 }
 
 void TabSearchPageHandler::NotifyTabsChanged() {
-  if (!browser_tab_strip_tracker_.is_processing_initial_browsers())
-    page_->TabsChanged();
+  page_->TabsChanged();
   debounce_timer_->Stop();
 }