Turn tab hover cards on by default on TOT.

Stable approval has been given for 76 in crbug/962604.

Bug: 910739
Change-Id: If66c3c8954794126ff194c3d681c3cc71ec20759
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1747977
Commit-Queue: Caroline Rising <corising@chromium.org>
Reviewed-by: Peter Boström <pbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#686596}

chrome/browser/ui/ui_features.cc

@@ -45,7 +45,7 @@ const base::Feature kTabGroups{"TabGroups", base::FEATURE_DISABLED_BY_DEFAULT};
 // Enables popup cards containing tab information when hovering over a tab.
 // https://crbug.com/910739
 const base::Feature kTabHoverCards{"TabHoverCards",
-                                   base::FEATURE_DISABLED_BY_DEFAULT};
+                                   base::FEATURE_ENABLED_BY_DEFAULT};
 // Parameter name used for tab hover cards user study.
 // TODO(corising): Removed this after tab hover cards user study.
 const char kTabHoverCardsFeatureParameterName[] = "setting";

chrome/browser/ui/views/tabs/tab_unittest.cc

@@ -15,6 +15,7 @@
 #include "chrome/browser/ui/tabs/tab_group_id.h"
 #include "chrome/browser/ui/tabs/tab_group_visual_data.h"
 #include "chrome/browser/ui/tabs/tab_utils.h"
+#include "chrome/browser/ui/ui_features.h"
 #include "chrome/browser/ui/views/tabs/alert_indicator.h"
 #include "chrome/browser/ui/views/tabs/fake_base_tab_strip_controller.h"
 #include "chrome/browser/ui/views/tabs/tab_close_button.h"
@@ -487,6 +488,10 @@ TEST_F(TabTest, LayoutAndVisibilityOfElements) {
 // Regression test for http://crbug.com/420313: Confirms that any child Views of
 // Tab do not attempt to provide their own tooltip behavior/text.
 TEST_F(TabTest, TooltipProvidedByTab) {
+  // This test isn't relevant when tab hover cards are enabled since tab
+  // tooltips are then disabled.
+  if (base::FeatureList::IsEnabled(features::kTabHoverCards))
+    return;
   Widget widget;
   InitWidget(&widget);
 
@@ -501,9 +506,9 @@ TEST_F(TabTest, TooltipProvidedByTab) {
   data.favicon = gfx::ImageSkia::CreateFrom1xBitmap(bitmap);
 
   data.title = base::UTF8ToUTF16(
-      "This is a really long tab title that would case views::Label to provide "
-      "its own tooltip; but Tab should disable that feature so it can provide "
-      "the tooltip instead.");
+      "This is a really long tab title that would cause views::Label to "
+      "provide its own tooltip; but Tab should disable that feature so it can "
+      "provide the tooltip instead.");
 
   // Test both with and without an indicator showing since the tab tooltip text
   // should include a description of the alert state when the indicator is