RenderTextHarfBuzz: Add support for multi line text selection.

ui/views/controls/label_unittest.cc

 // Copyright (c) 2012 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 "ui/views/controls/label.h"
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/i18n/rtl.h"
@@ skipping 802 matching lines @@
   EXPECT_LT(label()->font_list().GetHeight(), focus_bounds.height());
 }
 
 TEST_F(LabelSelectionTest, Selectable) {
   // By default, labels don't support text selection.
   EXPECT_FALSE(label()->selectable());
 
   ASSERT_TRUE(label()->SetSelectable(true));
   EXPECT_TRUE(label()->selectable());
 
-  // Verify that making a label multiline causes the label to not support text
+  // Verify that making a label multiline still causes the label to support text
   // selection.
   label()->SetMultiLine(true);
-  EXPECT_FALSE(label()->selectable());
-
-  label()->SetMultiLine(false);
-  ASSERT_TRUE(label()->SetSelectable(true));
   EXPECT_TRUE(label()->selectable());
 
   // Verify that obscuring the label text causes the label to not support text
   // selection.
   label()->SetObscured(true);
   EXPECT_FALSE(label()->selectable());
 }
 
 // Verify that labels supporting text selection get focus on clicks.
 TEST_F(LabelSelectionTest, FocusOnClick) {
@@ skipping 194 matching lines @@
   label()->SetObscured(false);
 
   // For an empty label, both COPY and SELECT_ALL should be disabled.
   label()->SetText(base::string16());
   ASSERT_TRUE(label()->SetSelectable(true));
   EXPECT_FALSE(IsMenuCommandEnabled(IDS_APP_COPY));
   EXPECT_FALSE(IsMenuCommandEnabled(IDS_APP_SELECT_ALL));
 }
 
 }  // namespace views