Added check for existance of the FindBarController before causing it to be...

Added check for existance of the FindBarController before causing it to be created on demand. This should prevent a startup performance regression.

Bug: 783350
Change-Id: Idbf4243e22db833fba8123c6b9e828c8c953ff12
Reviewed-on: https://chromium-review.googlesource.com/764030Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Evan Stade <estade@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Commit-Queue: Allen Bauer <kylixrd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517441}

chrome/browser/ui/find_bar/find_bar_controller_browsertest.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/ui/browser.h"
+#include "chrome/browser/ui/find_bar/find_bar_controller.h"
+#include "chrome/test/base/in_process_browser_test.h"
+
+using FindBarControllerTest = InProcessBrowserTest;
+
+// Creating the FindBarController on startup can result in a startup performance
+// regression. This test ensures that the FindBarController isn't created until
+// truly needed. See https://crbug.com/783350.
+IN_PROC_BROWSER_TEST_F(FindBarControllerTest,
+                       NoFindBarControllerOnBrowserCreate) {
+  // FindBarController should not be created on browser start.
+  EXPECT_FALSE(browser()->HasFindBarController());
+  // GetFindBarController should create the FindBarController on demand.
+  EXPECT_NE(nullptr, browser()->GetFindBarController());
+  // This should now indicate that there is now a FindBarController instance.
+  EXPECT_TRUE(browser()->HasFindBarController());
+}

chrome/browser/ui/views/location_bar/location_bar_view.cc

@@ -764,8 +764,13 @@ bool LocationBarView::RefreshSaveCreditCardIconView() {
 }
 
 bool LocationBarView::RefreshFindBarIcon() {
-  if (!find_bar_icon_ || !browser_ || !browser_->window())
+  // |browser_| may be nullptr since some unit tests pass it in for the
+  // Browser*. |browser_->window()| may return nullptr because Update() is
+  // called while BrowserWindow is being constructed.
+  if (!find_bar_icon_ || !browser_ || !browser_->window() ||
+      !browser_->HasFindBarController()) {
     return false;
+  }
   const bool was_visible = find_bar_icon_->visible();
   find_bar_icon_->SetVisible(
       browser_->GetFindBarController()->find_bar()->IsFindBarVisible());

chrome/test/BUILD.gn

@@ -731,6 +731,7 @@ test("browser_tests") {
       "../browser/ui/extensions/extension_message_bubble_browsertest.cc",
       "../browser/ui/extensions/extension_message_bubble_browsertest.h",
       "../browser/ui/extensions/hosted_app_browsertest.cc",
+      "../browser/ui/find_bar/find_bar_controller_browsertest.cc",
       "../browser/ui/find_bar/find_bar_host_browsertest.cc",
       "../browser/ui/hung_renderer_browsertest.cc",
       "../browser/ui/javascript_dialogs/javascript_dialog_browsertest.cc",