Clear the text cache when the tooltip text is updated.

chrome/browser/ui/views/bookmarks/bookmark_bar_view_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/views/bookmarks/bookmark_bar_view.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "chrome/browser/bookmarks/bookmark_model_factory.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/views/bookmarks/bookmark_bar_view_test_helper.h"
+#include "chrome/browser/ui/views/frame/browser_view.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "components/bookmarks/browser/bookmark_model.h"
+#include "components/bookmarks/test/bookmark_test_helpers.h"
+#include "ui/gfx/geometry/point.h"
+#include "ui/views/controls/button/label_button.h"
+
+dusing BookmarkBarViewTest = InProcessBrowserTest;
+
+IN_PROC_BROWSER_TEST_F(BookmarkBarViewTest, UpdateTooltipText) {

[sky, 2017/02/09 20:30:40]

Are you sure you need a browsertest for this? I'm wondering if you can use a
unit test.

[oshima, 2017/02/13 04:37:24]

I moved to unit test. I had to create a fake widget because a browser in
BrowserWithTestWindowTest has no views in it. Let me know if there is a better
way.

+  BrowserView* browser_view = static_cast<BrowserView*>(browser()->window());
+  BookmarkBarViewTestHelper helper(browser_view->bookmark_bar());
+  bookmarks::BookmarkModel* model =
+      BookmarkModelFactory::GetForBrowserContext(browser()->profile());
+  bookmarks::test::AddNodesFromModelString(model, model->bookmark_bar_node(),
+                                           "a b");
+  ASSERT_EQ(1, helper.GetBookmarkButtonCount());
+
+  views::LabelButton* button = helper.GetBookmarkButton(0);
+
+  gfx::Point p;
+  base::string16 text;
+  button->GetTooltipText(p, &text);
+  EXPECT_EQ(base::ASCIIToUTF16("a\na.com"), text);
+  button->SetText(base::ASCIIToUTF16("new title"));
+  button->GetTooltipText(p, &text);
+  EXPECT_EQ(base::ASCIIToUTF16("new title\na.com"), text);
+}