Introduce ui_test_utils::FocusView and de-flake OmniboxViewTest.BeginningShownAfterBlur

Currently interactive UI tests typically call `ClickOnView` to transfer
focus. On Mac, the behaviour of a click changes when an application
loses focus, and re-activating the application in a test is not
reliable. The test application shouldn't be losing focus in
interactive_ui_tests, but tracing suggests this is ocurring anyway.

This CL introduces ui_test_utils::FocusView which is a more robust way
to transfer focus in a test.

OmniboxViewTest.BeginningShownAfterBlur is changed to use
ui_test_utils::FocusView and re-enabled.

BUG=406012

Review URL: https://codereview.chromium.org/534993002

Cr-Commit-Position: refs/heads/master@{#293516}

chrome/browser/ui/omnibox/omnibox_view_browsertest.cc

@@ -1676,13 +1676,7 @@ IN_PROC_BROWSER_TEST_F(OmniboxViewTest, EditSearchEngines) {
   EXPECT_FALSE(omnibox_view->model()->popup_model()->IsOpen());
 }
 
-#if defined(OS_MACOSX)
-// http://crbug.com/406012
-#define MAYBE_BeginningShownAfterBlur DISABLED_BeginningShownAfterBlur
-#else
-#define MAYBE_BeginningShownAfterBlur BeginningShownAfterBlur
-#endif
-IN_PROC_BROWSER_TEST_F(OmniboxViewTest, MAYBE_BeginningShownAfterBlur) {
+IN_PROC_BROWSER_TEST_F(OmniboxViewTest, BeginningShownAfterBlur) {
   OmniboxView* omnibox_view = NULL;
   ASSERT_NO_FATAL_FAILURE(GetOmniboxView(&omnibox_view));
 
@@ -1690,18 +1684,18 @@ IN_PROC_BROWSER_TEST_F(OmniboxViewTest, MAYBE_BeginningShownAfterBlur) {
   omnibox_view->SetWindowTextAndCaretPos(ASCIIToUTF16("data:text/plain,test"),
       5U, false, false);
   omnibox_view->OnAfterPossibleChange();
-  ASSERT_TRUE(ui_test_utils::IsViewFocused(browser(), VIEW_ID_OMNIBOX));
+  EXPECT_TRUE(ui_test_utils::IsViewFocused(browser(), VIEW_ID_OMNIBOX));
   size_t start, end;
   omnibox_view->GetSelectionBounds(&start, &end);
-  ASSERT_EQ(5U, start);
-  ASSERT_EQ(5U, end);
+  EXPECT_EQ(5U, start);
+  EXPECT_EQ(5U, end);
 
-  ui_test_utils::ClickOnView(browser(), VIEW_ID_TAB_CONTAINER);
-  ASSERT_FALSE(ui_test_utils::IsViewFocused(browser(), VIEW_ID_OMNIBOX));
+  ui_test_utils::FocusView(browser(), VIEW_ID_TAB_CONTAINER);
+  EXPECT_FALSE(ui_test_utils::IsViewFocused(browser(), VIEW_ID_OMNIBOX));
 
   omnibox_view->GetSelectionBounds(&start, &end);
-  ASSERT_EQ(0U, start);
-  ASSERT_EQ(0U, end);
+  EXPECT_EQ(0U, start);
+  EXPECT_EQ(0U, end);
 }
 
 IN_PROC_BROWSER_TEST_F(OmniboxViewTest, CtrlArrowAfterArrowSuggestions) {

chrome/test/base/interactive_test_utils.h

@@ -31,6 +31,9 @@ bool IsViewFocused(const Browser* browser, ViewID vid);
 // Simulates a mouse click on a View in the browser.
 void ClickOnView(const Browser* browser, ViewID vid);
 
+// Makes focus shift to the given View without clicking it.
+void FocusView(const Browser* browser, ViewID vid);
+
 // A collection of utilities that are used from interactive_ui_tests. These are
 // separated from ui_test_utils.h to ensure that browser_tests don't use them,
 // since they depend on focus which isn't possible for sharded test.

chrome/test/base/interactive_test_utils_mac.mm

@@ -78,6 +78,14 @@ void ClickOnView(const Browser* browser, ViewID vid) {
   content::RunMessageLoop();
 }
 
+void FocusView(const Browser* browser, ViewID vid) {
+   NSWindow* window = browser->window()->GetNativeWindow();
+   DCHECK(window);
+   NSView* view = view_id_util::GetView(window, vid);
+   DCHECK(view);
+   [window makeFirstResponder:view];
+ }
+
 void HideNativeWindow(gfx::NativeWindow window) {
   [window orderOut:nil];
 }

chrome/test/base/interactive_test_utils_views.cc

@@ -43,6 +43,13 @@ void ClickOnView(const Browser* browser, ViewID vid) {
   content::RunMessageLoop();
 }
 
+void FocusView(const Browser* browser, ViewID vid) {
+  views::View* view =
+      BrowserView::GetBrowserViewForBrowser(browser)->GetViewByID(vid);
+  DCHECK(view);
+  view->RequestFocus();
+}
+
 #endif  // defined(OS_MACOSX)
 
 void MoveMouseToCenterAndPress(views::View* view,