Media Controls: Enable overflow icons by default 🚀

As the experiment was successful we are now proceeding with the launch
of the overflow icons. This switches them on by default.

BUG=763301

Change-Id: If3f2cf5dc4537a7fa700c56775827ccb4cd4663d
Reviewed-on: https://chromium-review.googlesource.com/970342
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544713}

media/base/media_switches.cc

@@ -359,9 +359,8 @@ MEDIA_EXPORT bool IsAudioFocusDuckFlashEnabled() {
 #endif  // BUILDFLAG(ENABLE_PLUGINS)
 
 // Adds icons to the overflow menu on the native media controls.
-// For experiment: crbug.com/763301
 const base::Feature kOverflowIconsForMediaControls{
-    "OverflowIconsForMediaControls", base::FEATURE_DISABLED_BY_DEFAULT};
+    "OverflowIconsForMediaControls", base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Enables the new redesigned media controls.
 const base::Feature kUseModernMediaControls{"UseModernMediaControls",

third_party/WebKit/LayoutTests/http/tests/media/controls/video-controls-overflow-menu-correct-ordering.html

@@ -35,8 +35,8 @@ async_test(function(t) {
       assert_equals(internals.shadowPseudoId(innerButton), overflowButtonsCSS[i]);
       // Items should be visible
       assert_not_equals(getComputedStyle(child).display, "none");
-      // Buttons shouldn't be visible
-      assert_equals(getComputedStyle(innerButton).display, "none");
+      // Buttons should be visible
+      assert_equals(getComputedStyle(innerButton).display, "flex");
     }
   });
 });