Activate comboboxes (i.e. open dropdown menu) on Enter and Space.

ui/views/controls/combobox/combobox_unittest.cc

 // Copyright 2013 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/combobox/combobox.h"
 
 #include <set>
 
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 608 matching lines @@
   PerformMousePress(left_point);
   PerformMouseRelease(left_point);
 
   EXPECT_EQ(1, menu_show_count);  // Unchanged.
   EXPECT_EQ(0, listener.perform_action_index());
 }
 
 TEST_F(ComboboxTest, ConsumingPressKeyEvents) {
   InitCombobox(nullptr, Combobox::STYLE_NORMAL);
 
-  EXPECT_FALSE(combobox_->OnKeyPressed(
+  int menu_show_count = 0;
+  test_api_->InstallTestMenuRunner(&menu_show_count);
+  EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_RETURN, ui::EF_NONE)));
-  EXPECT_FALSE(combobox_->OnKeyPressed(
+  EXPECT_EQ(1, menu_show_count);
+  EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_SPACE, ui::EF_NONE)));
+  EXPECT_EQ(2, menu_show_count);
 }
 
 TEST_F(ComboboxTest, ConsumingKeyPressEventsActionStyle) {
   // When the combobox's style is STYLE_ACTION, pressing events of a space key
   // or an enter key will be consumed.
   InitCombobox(nullptr, Combobox::STYLE_ACTION);
   EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_RETURN, ui::EF_NONE)));
   EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_SPACE, ui::EF_NONE)));
@@ skipping 170 matching lines @@
   EXPECT_EQ(ui::MenuModel::TYPE_COMMAND, menu_model->GetTypeAt(0));
   EXPECT_EQ(ui::MenuModel::TYPE_COMMAND, menu_model->GetTypeAt(1));
 
   EXPECT_EQ(ASCIIToUTF16("PEANUT BUTTER"), menu_model->GetLabelAt(0));
   EXPECT_EQ(ASCIIToUTF16("JELLY"), menu_model->GetLabelAt(1));
   EXPECT_FALSE(menu_model->IsVisibleAt(0));
   EXPECT_TRUE(menu_model->IsVisibleAt(1));
 }
 
 }  // namespace views