MacViews: Correct combobox unittests so that they terminate correctly.

On MacViews, the tests ComboboxTest.NotifyOnClickWithSpaceKey and
ComboboxTest.NotifyOnClickWithReturnKey do not terminate currently when run
individually. This only happens on Mac, because on other platforms the combobox
dropdown menu is async (non-blocking). However on Mac, a native NSMenu is used
to show the combobox dropdown, which runs a nested message loop and hence is
blocking.

To solve, install a TestMenuRunner for all the tests using the ComboboxTest
fixture. This ensures that an actual menu is not created.

BUG=679980
TEST= Run out/Default/views_unittests
--gtest_filter="ComboboxTest.NotifyOnClickWithSpaceKey" on Mac. Ensure that the
test terminates normally.

Review-Url: https://codereview.chromium.org/2620963002
Cr-Commit-Position: refs/heads/master@{#443077}

ui/views/controls/combobox/combobox_unittest.cc

@@ -185,7 +185,7 @@ class TestComboboxListener : public views::ComboboxListener {
 
 class ComboboxTest : public ViewsTestBase {
  public:
-  ComboboxTest() : widget_(NULL), combobox_(NULL) {}
+  ComboboxTest() {}
 
   void TearDown() override {
     if (widget_)
@@ -202,6 +202,7 @@ class ComboboxTest : public ViewsTestBase {
     ASSERT_FALSE(combobox_);
     combobox_ = new TestCombobox(model_.get(), style);
     test_api_.reset(new ComboboxTestApi(combobox_));
+    test_api_->InstallTestMenuRunner(&menu_show_count_);
     combobox_->set_id(1);
 
     widget_ = new Widget;
@@ -254,15 +255,18 @@ class ComboboxTest : public ViewsTestBase {
   }
 
   // We need widget to populate wrapper class.
-  Widget* widget_;
+  Widget* widget_ = nullptr;
 
   // |combobox_| will be allocated InitCombobox() and then owned by |widget_|.
-  TestCombobox* combobox_;
+  TestCombobox* combobox_ = nullptr;
   std::unique_ptr<ComboboxTestApi> test_api_;
 
   // Combobox does not take ownership of the model, hence it needs to be scoped.
   std::unique_ptr<TestComboboxModel> model_;
 
+  // The current menu show count.
+  int menu_show_count_ = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ComboboxTest);
 };
@@ -503,17 +507,14 @@ TEST_F(ComboboxTest, Click) {
 
   TestComboboxListener listener;
   combobox_->set_listener(&listener);
-
   combobox_->Layout();
-  int menu_show_count = 0;
-  test_api_->InstallTestMenuRunner(&menu_show_count);
 
   // Click the left side. The menu is shown.
-  EXPECT_EQ(0, menu_show_count);
+  EXPECT_EQ(0, menu_show_count_);
   PerformClick(gfx::Point(combobox_->x() + 1,
                           combobox_->y() + combobox_->height() / 2));
   EXPECT_FALSE(listener.on_perform_action_called());
-  EXPECT_EQ(1, menu_show_count);
+  EXPECT_EQ(1, menu_show_count_);
 }
 
 TEST_F(ComboboxTest, ClickButDisabled) {
@@ -526,12 +527,10 @@ TEST_F(ComboboxTest, ClickButDisabled) {
   combobox_->SetEnabled(false);
 
   // Click the left side, but nothing happens since the combobox is disabled.
-  int menu_show_count = 0;
-  test_api_->InstallTestMenuRunner(&menu_show_count);
   PerformClick(gfx::Point(combobox_->x() + 1,
                           combobox_->y() + combobox_->height() / 2));
   EXPECT_FALSE(listener.on_perform_action_called());
-  EXPECT_EQ(0, menu_show_count);
+  EXPECT_EQ(0, menu_show_count_);
 }
 
 TEST_F(ComboboxTest, NotifyOnClickWithReturnKey) {
@@ -540,8 +539,9 @@ TEST_F(ComboboxTest, NotifyOnClickWithReturnKey) {
   TestComboboxListener listener;
   combobox_->set_listener(&listener);
 
-  // With STYLE_NORMAL, the click event is ignored.
+  // With STYLE_NORMAL, the click event is ignored. Instead the menu is shown.
   SendKeyEvent(ui::VKEY_RETURN);
+  EXPECT_EQ(1, menu_show_count_);
   EXPECT_FALSE(listener.on_perform_action_called());
 }
 
@@ -551,8 +551,9 @@ TEST_F(ComboboxTest, NotifyOnClickWithReturnKeyActionStyle) {
   TestComboboxListener listener;
   combobox_->set_listener(&listener);
 
-  // With STYLE_ACTION, the click event is notified.
+  // With STYLE_ACTION, the click event is notified and the menu is not shown.
   SendKeyEvent(ui::VKEY_RETURN);
+  EXPECT_EQ(0, menu_show_count_);
   EXPECT_TRUE(listener.on_perform_action_called());
   EXPECT_EQ(0, listener.perform_action_index());
 }
@@ -563,10 +564,13 @@ TEST_F(ComboboxTest, NotifyOnClickWithSpaceKey) {
   TestComboboxListener listener;
   combobox_->set_listener(&listener);
 
-  // With STYLE_NORMAL, the click event is ignored.
+  // With STYLE_NORMAL, the click event is ignored. Instead the menu is shwon.
   SendKeyEvent(ui::VKEY_SPACE);
+  EXPECT_EQ(1, menu_show_count_);
   EXPECT_FALSE(listener.on_perform_action_called());
+
   SendKeyEventWithType(ui::VKEY_SPACE, ui::ET_KEY_RELEASED);
+  EXPECT_EQ(1, menu_show_count_);
   EXPECT_FALSE(listener.on_perform_action_called());
 }
 
@@ -576,10 +580,14 @@ TEST_F(ComboboxTest, NotifyOnClickWithSpaceKeyActionStyle) {
   TestComboboxListener listener;
   combobox_->set_listener(&listener);
 
-  // With STYLE_ACTION, the click event is notified after releasing.
+  // With STYLE_ACTION, the click event is notified after releasing and the menu
+  // is not shown.
   SendKeyEvent(ui::VKEY_SPACE);
+  EXPECT_EQ(0, menu_show_count_);
   EXPECT_FALSE(listener.on_perform_action_called());
+
   SendKeyEventWithType(ui::VKEY_SPACE, ui::ET_KEY_RELEASED);
+  EXPECT_EQ(0, menu_show_count_);
   EXPECT_TRUE(listener.on_perform_action_called());
   EXPECT_EQ(0, listener.perform_action_index());
 }
@@ -593,12 +601,10 @@ TEST_F(ComboboxTest, NotifyOnClickWithMouse) {
   combobox_->Layout();
 
   // Click the right side (arrow button). The menu is shown.
-  int menu_show_count = 0;
-  test_api_->InstallTestMenuRunner(&menu_show_count);
   const gfx::Point right_point(combobox_->x() + combobox_->width() - 1,
                          combobox_->y() + combobox_->height() / 2);
 
-  EXPECT_EQ(0, menu_show_count);
+  EXPECT_EQ(0, menu_show_count_);
 
 // On Mac, actions occur on mouse down. Otherwise mouse up.
 #if defined(OS_MACOSX)
@@ -608,43 +614,43 @@ TEST_F(ComboboxTest, NotifyOnClickWithMouse) {
 #endif
 
   PerformMousePress(right_point);
-  EXPECT_EQ(kActOnMouseDown, menu_show_count);
+  EXPECT_EQ(kActOnMouseDown, menu_show_count_);
   PerformMouseRelease(right_point);
-  EXPECT_EQ(1, menu_show_count);
+  EXPECT_EQ(1, menu_show_count_);
 
   // Click the left side (text button). The click event is notified.
   const gfx::Point left_point(
       gfx::Point(combobox_->x() + 1, combobox_->y() + combobox_->height() / 2));
-  test_api_->InstallTestMenuRunner(&menu_show_count);
 
   PerformMousePress(left_point);
   PerformMouseRelease(left_point);
 
-  EXPECT_EQ(1, menu_show_count);  // Unchanged.
+  EXPECT_EQ(1, menu_show_count_);  // Unchanged.
   EXPECT_EQ(0, listener.perform_action_index());
 }
 
 TEST_F(ComboboxTest, ConsumingPressKeyEvents) {
   InitCombobox(nullptr, Combobox::STYLE_NORMAL);
 
-  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_EQ(1, menu_show_count);
+  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);
+  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.
+  // or an enter key will be consumed and the menu is not shown.
   InitCombobox(nullptr, Combobox::STYLE_ACTION);
+
   EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_RETURN, ui::EF_NONE)));
+  EXPECT_EQ(0, menu_show_count_);
   EXPECT_TRUE(combobox_->OnKeyPressed(
       ui::KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_SPACE, ui::EF_NONE)));
+  EXPECT_EQ(0, menu_show_count_);
 }
 
 TEST_F(ComboboxTest, ContentWidth) {