Re-add backspace-goes-back as a default disabled finch trial

chrome/browser/ui/views/constrained_window_views_browsertest.cc

Index: chrome/browser/ui/views/constrained_window_views_browsertest.cc
diff --git a/chrome/browser/ui/views/constrained_window_views_browsertest.cc b/chrome/browser/ui/views/constrained_window_views_browsertest.cc
index b842745b5914734ad94eba229f87be018a43124c..efdf105265948db499e9773d5777336393a3268d 100644
--- a/chrome/browser/ui/views/constrained_window_views_browsertest.cc
+++ b/chrome/browser/ui/views/constrained_window_views_browsertest.cc
@@ -168,6 +168,53 @@ IN_PROC_BROWSER_TEST_F(ConstrainedWindowViewTest, TabMoveTest) {
   EXPECT_EQ(NULL, dialog->GetWidget());
 }
 
+// Tests that the web contents navigates when backspace is pressed.
+IN_PROC_BROWSER_TEST_F(ConstrainedWindowViewTest, NavigationOnBackspace) {
+  content::WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  content::WaitForLoadStop(web_contents);
+  const GURL original_url = web_contents->GetURL();
+  EXPECT_NE(GURL(chrome::kChromeUIVersionURL), original_url);
+  ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIVersionURL));
+  content::WaitForLoadStop(web_contents);
+  EXPECT_EQ(GURL(chrome::kChromeUIVersionURL), web_contents->GetURL());
+
+  std::unique_ptr<TestDialog> dialog = ShowModalDialog(web_contents);
+
+  views::Widget* widget = dialog->GetWidget();
+
+  EXPECT_TRUE(widget->IsVisible());
+  EXPECT_EQ(dialog->GetContentsView(),
+            widget->GetFocusManager()->GetFocusedView());
+
+  // Pressing backspace should not navigate back and close the dialog
+  // with the Finch flag disabled.
+  EXPECT_TRUE(chrome::CanGoBack(browser()));
+  EXPECT_TRUE(ui_test_utils::SendKeyPressSync(browser(), ui::VKEY_BACK,
+                                              false, false, false, false));
+  content::RunAllPendingInMessageLoop();
+  content::WaitForLoadStop(web_contents);
+
+  EXPECT_EQ(widget, dialog->GetWidget());
+  EXPECT_EQ(GURL(chrome::kChromeUIVersionURL), web_contents->GetURL());
+
+  // Pressing backspace should navigate back and close the dialog with the
+  // Finch flag enabled.
+  base::FeatureList::ClearInstanceForTesting();
+  std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
+  feature_list->InitializeFromCommandLine("BackspaceGoesBack", std::string());
+  base::FeatureList::SetInstance(std::move(feature_list));
+
+  EXPECT_TRUE(chrome::CanGoBack(browser()));
+  EXPECT_TRUE(ui_test_utils::SendKeyPressSync(browser(), ui::VKEY_BACK,
+                                              false, false, false, false));
+  content::RunAllPendingInMessageLoop();
+  content::WaitForLoadStop(web_contents);
+
+  EXPECT_EQ(nullptr, dialog->GetWidget());
+  EXPECT_EQ(original_url, web_contents->GetURL());
+}
+
 // Tests that the dialog closes when the escape key is pressed.
 IN_PROC_BROWSER_TEST_F(ConstrainedWindowViewTest, ClosesOnEscape) {
 #if defined(OS_WIN)