Code Health: Clean up stale MacWebContentsOcclusion

Fixed: 362247468
Change-Id: I1ac6f1427cfc4aa1d2b9de60c52b7b7849a45f1a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6078344
Commit-Queue: Nathan Memmott <memmott@chromium.org>
Reviewed-by: Jayson Adams <shrike@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1395120}

content/app_shim_remote_cocoa/web_contents_occlusion_checker_mac.h

@@ -12,8 +12,6 @@
 #import "content/app_shim_remote_cocoa/web_contents_view_cocoa.h"
 #include "content/common/web_contents_ns_view_bridge.mojom.h"
 
-extern CONTENT_EXPORT const base::FeatureParam<bool>
-    kEnhancedWindowOcclusionDetection;
 extern CONTENT_EXPORT const base::FeatureParam<bool>
     kDisplaySleepAndAppHideDetection;
 

content/app_shim_remote_cocoa/web_contents_occlusion_checker_mac.mm

@@ -19,12 +19,6 @@
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/common/content_client.h"
 
-using features::kMacWebContentsOcclusion;
-
-// Experiment features.
-const base::FeatureParam<bool> kEnhancedWindowOcclusionDetection{
-    &kMacWebContentsOcclusion, "EnhancedWindowOcclusionDetection", false};
-
 namespace {
 
 NSString* const kWindowDidChangePositionInWindowList =
@@ -98,7 +92,6 @@ bool IsBrowserProcess() {
 - (instancetype)init {
   self = [super init];
 
-  DCHECK(base::FeatureList::IsEnabled(kMacWebContentsOcclusion));
   DCHECK(IsBrowserProcess());
   if (!IsBrowserProcess()) {
     static auto* const crash_key = base::debug::AllocateCrashKeyString(
@@ -134,8 +127,7 @@ bool IsBrowserProcess() {
 
 - (BOOL)isManualOcclusionDetectionEnabled {
   return [WebContentsOcclusionCheckerMac
-             manualOcclusionDetectionSupportedForCurrentMacOSVersion] &&
+      manualOcclusionDetectionSupportedForCurrentMacOSVersion];
-         kEnhancedWindowOcclusionDetection.Get();
 }
 
 // Alternative implementation of orderWindow:relativeTo:. Replaces

content/app_shim_remote_cocoa/web_contents_view_cocoa.mm

@@ -29,7 +29,6 @@
 #include "ui/resources/grit/ui_resources.h"
 
 using content::DropData;
-using features::kMacWebContentsOcclusion;
 using remote_cocoa::mojom::DraggingInfo;
 using remote_cocoa::mojom::SelectionDirection;
 
@@ -127,17 +126,12 @@ STATIC_ASSERT_ENUM(NSDragOperationMove, ui::DragDropTypes::DRAG_MOVE);
 
   gfx::Rect _windowControlsOverlayRect;
 
-  // TODO(crbug.com/40593221): Remove this when kMacWebContentsOcclusion
-  // is enabled by default.
-  BOOL _inFullScreenTransition;
   BOOL _willSetWebContentsOccludedAfterDelay;
 }
 
 + (void)initialize {
-  if (base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
+  // Create the WebContentsOcclusionCheckerMac shared instance.
-    // Create the WebContentsOcclusionCheckerMac shared instance.
+  [WebContentsOcclusionCheckerMac sharedInstance];
-    [WebContentsOcclusionCheckerMac sharedInstance];
-  }
 }
 
 - (instancetype)initWithViewsHostableView:(ui::ViewsHostableView*)v {
@@ -440,7 +434,6 @@ STATIC_ASSERT_ENUM(NSDragOperationMove, ui::DragDropTypes::DRAG_MOVE);
     (remote_cocoa::mojom::Visibility)visibility {
   using remote_cocoa::mojom::Visibility;
 
-  DCHECK(base::FeatureList::IsEnabled(kMacWebContentsOcclusion));
   if (!_host)
     return;
 
@@ -486,21 +479,6 @@ STATIC_ASSERT_ENUM(NSDragOperationMove, ui::DragDropTypes::DRAG_MOVE);
   [self updateWebContentsVisibility:visibility];
 }
 
-- (void)legacyUpdateWebContentsVisibility {
-  using remote_cocoa::mojom::Visibility;
-  DCHECK(!base::FeatureList::IsEnabled(kMacWebContentsOcclusion));
-  if (!_host || _inFullScreenTransition)
-    return;
-  Visibility visibility = Visibility::kVisible;
-  if ([self isHiddenOrHasHiddenAncestor] || ![self window])
-    visibility = Visibility::kHidden;
-  else if ([[self window] occlusionState] & NSWindowOcclusionStateVisible)
-    visibility = Visibility::kVisible;
-  else
-    visibility = Visibility::kOccluded;
-  _host->OnWindowVisibilityChanged(visibility);
-}
-
 - (void)resizeSubviewsWithOldSize:(NSSize)oldBoundsSize {
   // Subviews do not participate in auto layout unless the the size this view
   // changes. This allows RenderWidgetHostViewMac::SetBounds(..) to select a
@@ -523,72 +501,22 @@ STATIC_ASSERT_ENUM(NSDragOperationMove, ui::DragDropTypes::DRAG_MOVE);
 
   NSWindow* oldWindow = [self window];
 
-  if (base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
-    if (oldWindow) {
-      [notificationCenter
-          removeObserver:self
-                    name:NSWindowDidChangeOcclusionStateNotification
-                  object:oldWindow];
-    }
-
-    if (newWindow) {
-      [notificationCenter
-          addObserver:self
-             selector:@selector(windowChangedOcclusionState:)
-                 name:NSWindowDidChangeOcclusionStateNotification
-               object:newWindow];
-    }
-
-    return;
-  }
-
-  _inFullScreenTransition = NO;
   if (oldWindow) {
-    NSArray* notificationsToRemove = @[
+    [notificationCenter
-      NSWindowDidChangeOcclusionStateNotification,
+        removeObserver:self
-      NSWindowWillEnterFullScreenNotification,
+                  name:NSWindowDidChangeOcclusionStateNotification
-      NSWindowDidEnterFullScreenNotification,
+                object:oldWindow];
-      NSWindowWillExitFullScreenNotification,
-      NSWindowDidExitFullScreenNotification
-    ];
-    for (NSString* notificationName in notificationsToRemove) {
-      [notificationCenter removeObserver:self
-                                    name:notificationName
-                                  object:oldWindow];
-    }
   }
+
   if (newWindow) {
     [notificationCenter addObserver:self
                            selector:@selector(windowChangedOcclusionState:)
                                name:NSWindowDidChangeOcclusionStateNotification
                              object:newWindow];
-    // The fullscreen transition causes spurious occlusion notifications.
-    // See https://crbug.com/1081229
-    [notificationCenter addObserver:self
-                           selector:@selector(fullscreenTransitionStarted:)
-                               name:NSWindowWillEnterFullScreenNotification
-                             object:newWindow];
-    [notificationCenter addObserver:self
-                           selector:@selector(fullscreenTransitionComplete:)
-                               name:NSWindowDidEnterFullScreenNotification
-                             object:newWindow];
-    [notificationCenter addObserver:self
-                           selector:@selector(fullscreenTransitionStarted:)
-                               name:NSWindowWillExitFullScreenNotification
-                             object:newWindow];
-    [notificationCenter addObserver:self
-                           selector:@selector(fullscreenTransitionComplete:)
-                               name:NSWindowDidExitFullScreenNotification
-                             object:newWindow];
   }
 }
 
 - (void)windowChangedOcclusionState:(NSNotification*)aNotification {
-  if (!base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
-    [self legacyUpdateWebContentsVisibility];
-    return;
-  }
-
   // Only respond to occlusion notifications sent by the occlusion checker.
   NSDictionary* userInfo = [aNotification userInfo];
   NSString* occlusionCheckerKey = [WebContentsOcclusionCheckerMac className];
@@ -596,40 +524,15 @@ STATIC_ASSERT_ENUM(NSDragOperationMove, ui::DragDropTypes::DRAG_MOVE);
     [self updateWebContentsVisibility];
 }
 
-- (void)fullscreenTransitionStarted:(NSNotification*)notification {
-  DCHECK(!base::FeatureList::IsEnabled(kMacWebContentsOcclusion));
-  _inFullScreenTransition = YES;
-}
-
-- (void)fullscreenTransitionComplete:(NSNotification*)notification {
-  DCHECK(!base::FeatureList::IsEnabled(kMacWebContentsOcclusion));
-  _inFullScreenTransition = NO;
-}
-
 - (void)viewDidMoveToWindow {
-  if (!base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
-    [self legacyUpdateWebContentsVisibility];
-    return;
-  }
-
   [self updateWebContentsVisibility];
 }
 
 - (void)viewDidHide {
-  if (!base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
-    [self legacyUpdateWebContentsVisibility];
-    return;
-  }
-
   [self updateWebContentsVisibility];
 }
 
 - (void)viewDidUnhide {
-  if (!base::FeatureList::IsEnabled(kMacWebContentsOcclusion)) {
-    [self legacyUpdateWebContentsVisibility];
-    return;
-  }
-
   [self updateWebContentsVisibility];
 }
 

content/app_shim_remote_cocoa/window_occlusion_browsertest_mac.mm

@@ -16,19 +16,15 @@
 #include "content/public/test/browser_test.h"
 #include "content/public/test/content_browser_test.h"
 
+using content::DropData;
 using remote_cocoa::mojom::DraggingInfo;
 using remote_cocoa::mojom::DraggingInfoPtr;
 using remote_cocoa::mojom::SelectionDirection;
-using content::DropData;
 
 namespace {
 
 const int kNeverCalled = -100;
 
-struct FeatureState {
-  bool enhanced_occlusion_detection_enabled = false;
-};
-
 struct Version {
   int packed_version;
   bool supported;
@@ -333,21 +329,8 @@ class WebContentsNSViewHostStub
 };
 
 // Sets up occlusion tests.
-class WindowOcclusionBrowserTestMac
+class WindowOcclusionBrowserTestMac : public ContentBrowserTest {
-    : public ::testing::WithParamInterface<FeatureState>,
-      public ContentBrowserTest {
  public:
-  WindowOcclusionBrowserTestMac() {
-    if (GetParam().enhanced_occlusion_detection_enabled) {
-      base::FieldTrialParams params;
-      params["EnhancedWindowOcclusionDetection"] = "true";
-      features_.InitAndEnableFeatureWithParameters(
-          features::kMacWebContentsOcclusion, params);
-    } else {
-      features_.InitAndDisableFeature(features::kMacWebContentsOcclusion);
-    }
-  }
-
   void SetUp() override {
     if (![NSClassFromString(@"WebContentsOcclusionCheckerMac")
             manualOcclusionDetectionSupportedForCurrentMacOSVersion]) {
@@ -397,9 +380,6 @@ class WindowOcclusionBrowserTestMac
   }
 
   void WaitForOcclusionUpdate() {
-    if (!base::FeatureList::IsEnabled(features::kMacWebContentsOcclusion))
-      return;
-
     while ([[NSClassFromString(@"WebContentsOcclusionCheckerMac")
                sharedInstance] occlusionStateUpdatesAreScheduledForTesting] ||
            WebContentsAwaitingUpdates()) {
@@ -480,16 +460,10 @@ class WindowOcclusionBrowserTestMac
   void OrderWindowFront(NSWindow* window) {
     [[maybe_unused]] WebContentVisibilityUpdateCounter* watcher;
 
-    if (!kEnhancedWindowOcclusionDetection.Get()) {
-      watcher = [[WebContentVisibilityUpdateCounter alloc] init];
-    }
-
     [window orderFront:nil];
     ASSERT_TRUE([window isVisible]);
 
-    if (kEnhancedWindowOcclusionDetection.Get()) {
+    WaitForOcclusionUpdate();
-      WaitForOcclusionUpdate();
-    }
   }
 
   void OrderWindowOut(NSWindow* window) {
@@ -575,34 +549,8 @@ class WindowOcclusionBrowserTestMac
   WebContentsNSViewHostStub host_a_;
 };
 
-using WindowOcclusionBrowserTestMacWithoutOcclusionFeature =
-    WindowOcclusionBrowserTestMac;
-using WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature =
-    WindowOcclusionBrowserTestMac;
-
-// Tests that should only work without the occlusion detection feature.
-INSTANTIATE_TEST_SUITE_P(NoFeature,
-                         WindowOcclusionBrowserTestMacWithoutOcclusionFeature,
-                         ::testing::Values(FeatureState{
-                             .enhanced_occlusion_detection_enabled = false}));
-
-// Tests that should work with or without the occlusion detection feature.
-INSTANTIATE_TEST_SUITE_P(
-    Common,
-    WindowOcclusionBrowserTestMac,
-    ::testing::Values(
-        FeatureState{.enhanced_occlusion_detection_enabled = false},
-        FeatureState{.enhanced_occlusion_detection_enabled = true}));
-
-// Tests that require enhanced window occlusion detection.
-INSTANTIATE_TEST_SUITE_P(
-    EnhancedWindowOcclusionDetection,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
-    ::testing::Values(FeatureState{
-        .enhanced_occlusion_detection_enabled = true}));
-
 // Tests that we correctly disallow unsupported macOS versions.
-IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac, MacOSVersionChecking) {
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac, MacOSVersionChecking) {
   Class WebContentsOcclusionCheckerMac =
       NSClassFromString(@"WebContentsOcclusionCheckerMac");
   std::vector<Version> versions = {
@@ -617,45 +565,8 @@ IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac, MacOSVersionChecking) {
   }
 }
 
-// Tests that enhanced occlusion detection isn't triggered if the feature's
-// not enabled.
-IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMacWithoutOcclusionFeature,
-                       ManualOcclusionDetectionDisabled) {
-  InitWindowA();
-
-  // Create a second window and place it exactly over window_a. The window
-  // should still be considered visible.
-  InitWindowB([window_a_ frame]);
-  EXPECT_EQ(WindowAWebContentsVisibility(),
-            remote_cocoa::mojom::Visibility::kVisible);
-}
-
-// Test that display sleep and app hide detection don't work if the feature's
-// not enabled.
-IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMacWithoutOcclusionFeature,
-                       OcclusionDetectionOnDisplaySleepDisabled) {
-  InitWindowA();
-
-  EXPECT_EQ(WindowAWebContentsVisibility(),
-            remote_cocoa::mojom::Visibility::kVisible);
-
-  // Fake a display sleep notification.
-  ASSERT_TRUE(NSWorkspace.sharedWorkspace.notificationCenter);
-  [[maybe_unused]] WebContentVisibilityUpdateCounter* watcher =
-      [[WebContentVisibilityUpdateCounter alloc] init];
-
-  [NSWorkspace.sharedWorkspace.notificationCenter
-      postNotificationName:NSWorkspaceScreensDidSleepNotification
-                    object:nil
-                  userInfo:nil];
-
-  EXPECT_TRUE([WebContentVisibilityUpdateCounter methodNeverCalled]);
-  EXPECT_EQ(WindowAWebContentsVisibility(),
-            remote_cocoa::mojom::Visibility::kVisible);
-}
-
 // Test that we properly handle occlusion notifications from macOS.
-IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac,
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
                        MacOSOcclusionNotifications) {
   InitWindowA();
 
@@ -672,9 +583,8 @@ IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac,
             remote_cocoa::mojom::Visibility::kVisible);
 }
 
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ManualOcclusionDetection) {
-    ManualOcclusionDetection) {
   InitWindowA();
 
   // Create a second window and place it exactly over window_a. Unlike macOS,
@@ -710,9 +620,8 @@ IN_PROC_BROWSER_TEST_P(
 }
 
 // Checks manual occlusion detection as windows change display order.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ManualOcclusionDetectionOnWindowOrderChange) {
-    ManualOcclusionDetectionOnWindowOrderChange) {
   InitWindowA();
 
   // Size and position the second window so that it exactly covers the
@@ -734,9 +643,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Checks that window_a, occluded by window_b, transitions to kVisible while the
 // user resizes window_b.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ManualOcclusionDetectionOnWindowLiveResize) {
-    ManualOcclusionDetectionOnWindowLiveResize) {
   InitWindowA();
 
   // Size and position the second window so that it exactly covers the
@@ -765,9 +673,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Checks that window_a, occluded by window_b, transitions to kVisible when
 // window_b is set to close.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ManualOcclusionDetectionOnWindowClose) {
-    ManualOcclusionDetectionOnWindowClose) {
   InitWindowA();
 
   // Size and position the second window so that it exactly covers the
@@ -788,9 +695,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Checks that window_a, occluded by window_b and window_c, remains kOccluded
 // when window_b is set to close.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ManualOcclusionDetectionOnMiddleWindowClose) {
-    ManualOcclusionDetectionOnMiddleWindowClose) {
   InitWindowA();
 
   // Size and position the second window so that it exactly covers the
@@ -821,9 +727,8 @@ IN_PROC_BROWSER_TEST_P(
 }
 
 // Checks that web contents are marked kHidden on display sleep.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       OcclusionDetectionOnDisplaySleep) {
-    OcclusionDetectionOnDisplaySleep) {
   InitWindowA();
 
   EXPECT_EQ(WindowAWebContentsVisibility(),
@@ -844,9 +749,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Checks that occlusion updates are ignored in between fullscreen transition
 // notifications.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(
     WindowOcclusionBrowserTestMac,
-    //                       WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
     IgnoreOcclusionUpdatesBetweenWindowFullscreenTransitionNotifications) {
   InitWindowA();
 
@@ -907,9 +811,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Tests that each web contents in a window receives an updated occlusion
 // state updated.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       OcclusionDetectionForMultipleWebContents) {
-    OcclusionDetectionForMultipleWebContents) {
   InitWindowA();
 
   EXPECT_EQ(WindowAWebContentsVisibility(),
@@ -960,7 +863,7 @@ IN_PROC_BROWSER_TEST_P(
 }
 
 // Checks that web contentses are marked kHidden on WebContentsViewCocoa hide.
-IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac,
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
                        OcclusionDetectionOnWebContentsViewCocoaHide) {
   InitWindowA();
 
@@ -987,7 +890,7 @@ IN_PROC_BROWSER_TEST_P(WindowOcclusionBrowserTestMac,
 
 // Checks that web contentses are marked kHidden on WebContentsViewCocoa removal
 // from the view hierarchy.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(
     WindowOcclusionBrowserTestMac,
     OcclusionDetectionOnWebContentsViewCocoaRemoveFromSuperview) {
   InitWindowA();
@@ -1024,9 +927,8 @@ IN_PROC_BROWSER_TEST_P(
 }
 
 // Checks that web contentses are marked kHidden on window miniaturize.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       OcclusionDetectionOnWindowMiniaturize) {
-    OcclusionDetectionOnWindowMiniaturize) {
   InitWindowA();
 
   EXPECT_EQ(WindowAWebContentsVisibility(),
@@ -1052,9 +954,8 @@ IN_PROC_BROWSER_TEST_P(
 // triggering a visibility update, which causes a visibility watcher to add
 // a second child window (while we're still inside AppKit code adding the
 // first).
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       ChildWindowListMutationDuringManualOcclusionDetection) {
-    ChildWindowListMutationDuringManualOcclusionDetection) {
   InitWindowA();
 
   const NSRect kContentRect = NSMakeRect(0.0, 0.0, 20.0, 20.0);
@@ -1083,9 +984,8 @@ IN_PROC_BROWSER_TEST_P(
 
 // Tests that when a window becomes a child, if the occlusion system
 // previously marked it occluded, the window transitions to visible.
-IN_PROC_BROWSER_TEST_P(
+IN_PROC_BROWSER_TEST_F(WindowOcclusionBrowserTestMac,
-    WindowOcclusionBrowserTestMacWithOcclusionDetectionFeature,
+                       WindowMadeChildForcedVisible) {
-    WindowMadeChildForcedVisible) {
   InitWindowA();
 
   // Create a second window that occludes window_a.

content/common/features.cc

@@ -305,14 +305,6 @@ BASE_FEATURE(kIOSurfaceCapturer,
              base::FEATURE_ENABLED_BY_DEFAULT);
 #endif
 
-// Feature that controls whether WebContentsOcclusionChecker should handle
-// occlusion notifications.
-#if BUILDFLAG(IS_MAC)
-BASE_FEATURE(kMacWebContentsOcclusion,
-             "MacWebContentsOcclusion",
-             base::FEATURE_ENABLED_BY_DEFAULT);
-#endif
-
 // If this feature is enabled, media-device enumerations use a cache that is
 // invalidated upon notifications sent by base::SystemMonitor. If disabled, the
 // cache is considered invalid on every enumeration request.

content/common/features.h

@@ -81,9 +81,6 @@ CONTENT_EXPORT BASE_DECLARE_FEATURE(kInterestGroupUpdateIfOlderThan);
 #if BUILDFLAG(IS_MAC)
 CONTENT_EXPORT BASE_DECLARE_FEATURE(kIOSurfaceCapturer);
 #endif
-#if BUILDFLAG(IS_MAC)
-CONTENT_EXPORT BASE_DECLARE_FEATURE(kMacWebContentsOcclusion);
-#endif
 CONTENT_EXPORT BASE_DECLARE_FEATURE(kMediaDevicesSystemMonitorCache);
 CONTENT_EXPORT BASE_DECLARE_FEATURE(kMediaStreamTrackTransfer);
 CONTENT_EXPORT BASE_DECLARE_FEATURE(kMojoDedicatedThread);

testing/variations/fieldtrial_testing_config.json

@@ -13443,24 +13443,6 @@
             ]
         }
     ],
-    "MacWebContentsOcclusionV2": [
-        {
-            "platforms": [
-                "mac"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled",
-                    "params": {
-                        "EnhancedWindowOcclusionDetection": "true"
-                    },
-                    "enable_features": [
-                        "MacWebContentsOcclusion"
-                    ]
-                }
-            ]
-        }
-    ],
     "MagicStackGradientView": [
         {
             "platforms": [