Fix tab hover card position in vertical tabs (#35246)

Resolves brave/brave-browser#54199

The hover card should sit to the right of the strip in vertical-tab mode (LEFT_TOP).
Brave only set the bubble arrow in BraveTabHoverCardController when the card
was created or when orientation changed.
Chromium keeps the arrow in sync from anchor_target->GetAnchorPosition() on every update,
so BraveTab still reporting TOP_LEFT could overwrite the correct arrow.

Override BraveTab::GetAnchorPosition() to return LEFT_TOP when vertical tabs are enabled,
otherwise use Tab::GetAnchorPosition().
Remove the controller’s SetIsVerticalTabs / UpdateHoverCardArrow path and the BraveTabStrip call.

TEST=BraveTabTest.GetAnchorPositionReflectsTabOrientation

browser/ui/views/tabs/brave_tab.cc

@@ -28,6 +28,7 @@
 #include "ui/base/models/image_model.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/views/animation/ink_drop.h"
+#include "ui/views/bubble/bubble_border.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/view_class_properties.h"
@@ -63,6 +64,15 @@ int BraveTab::GetTreeHeight() const {
   return 0;
 }
 
+views::BubbleBorder::Arrow BraveTab::GetAnchorPosition() const {
+  if (tabs::utils::ShouldShowBraveVerticalTabs(
+          controller()->GetBrowserWindowInterface())) {
+    return views::BubbleBorder::Arrow::LEFT_TOP;
+  }
+
+  return Tab::GetAnchorPosition();
+}
+
 std::u16string BraveTab::GetRenderedTooltipText(const gfx::Point& p) const {
   auto* browser = controller_->GetBrowserWindowInterface();
   if (browser &&

browser/ui/views/tabs/brave_tab.h

@@ -51,6 +51,7 @@ class BraveTab : public Tab {
   void UpdateTreeToggleButtonIcon();
 
   // Tab:
+  views::BubbleBorder::Arrow GetAnchorPosition() const override;
   std::u16string GetRenderedTooltipText(const gfx::Point& p) const override;
 
   // Overridden because we moved alert button to left side in the tab whereas

browser/ui/views/tabs/brave_tab_hover_card_controller.cc

@@ -16,25 +16,9 @@
 #include "chrome/browser/ui/views/tabs/tab_hover_card_controller.h"
 #include "chrome/browser/ui/views/tabs/tab_hover_card_thumbnail_observer.h"
 #include "chrome/browser/ui/views/tabs/tab_strip.h"
-#include "ui/views/bubble/bubble_border.h"
 
 BraveTabHoverCardController::~BraveTabHoverCardController() = default;
 
-void BraveTabHoverCardController::SetIsVerticalTabs(bool is_vertical_tabs) {
-  if (std::exchange(is_vertical_tabs_, is_vertical_tabs) == is_vertical_tabs) {
-    return;
-  }
-
-  UpdateHoverCardArrow();
-}
-
-void BraveTabHoverCardController::UpdateHoverCardArrow() {
-  if (hover_card_) {
-    hover_card_->SetArrow(is_vertical_tabs_ ? views::BubbleBorder::LEFT_TOP
-                                            : views::BubbleBorder::TOP_CENTER);
-  }
-}
-
 void BraveTabHoverCardController::CreateHoverCard(
     HoverCardAnchorTarget* anchor_target) {
   hover_card_image_previews_enabled_ =
@@ -43,8 +27,6 @@ void BraveTabHoverCardController::CreateHoverCard(
           browser_window_interface_->GetProfile()->GetPrefs());
 
   TabHoverCardController::CreateHoverCard(anchor_target);
-
-  UpdateHoverCardArrow();
 }
 
 void BraveTabHoverCardController::OnHovercardImagesEnabledChanged() {

browser/ui/views/tabs/brave_tab_hover_card_controller.h

@@ -15,17 +15,11 @@ class BraveTabHoverCardController : public TabHoverCardController {
   using TabHoverCardController::TabHoverCardController;
   ~BraveTabHoverCardController() override;
 
-  void SetIsVerticalTabs(bool is_vertical_tabs);
-
  protected:
-  void UpdateHoverCardArrow();
-
   void OnHovercardImagesEnabledChanged() override;
 
   // TabHoverCardController:
   void CreateHoverCard(HoverCardAnchorTarget* anchor_target) override;
-
-  bool is_vertical_tabs_ = false;
 };
 
 #endif  // BRAVE_BROWSER_UI_VIEWS_TABS_BRAVE_TAB_HOVER_CARD_CONTROLLER_H_

browser/ui/views/tabs/brave_tab_strip.cc

@@ -326,8 +326,6 @@ void BraveTabStrip::UpdateOrientation() {
     SetAvailableWidthCallback(base::NullCallback());
   }
 
-  hover_card_controller_->SetIsVerticalTabs(using_vertical_tabs);
-
   if (const auto active_index = GetActiveIndex(); active_index) {
     // In order to update shadow state, call ActiveStateChanged().
     tab_at(active_index.value())->ActiveStateChanged();

browser/ui/views/tabs/brave_tab_unittest.cc

@@ -28,6 +28,7 @@
 #include "ui/gfx/geometry/insets.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/skia_conversions.h"
+#include "ui/views/bubble/bubble_border.h"
 #include "ui/views/test/views_test_utils.h"
 
 class MockTabSlotController : public FakeTabSlotController {
@@ -521,3 +522,36 @@ TEST_F(BraveTabTest, GetTabSizeInfoFullMinWidthModeUsesStandardWidth) {
   EXPECT_EQ(info.min_active_width, std_w);
   EXPECT_EQ(info.min_inactive_width, std_w);
 }
+
+// BraveTab::GetAnchorPosition() must return LEFT_TOP in vertical tab mode so
+// that the hover card appears to the right of the tab strip, and must
+// delegate to Tab::GetAnchorPosition() (TOP_LEFT) in horizontal mode.
+TEST_F(BraveTabTest, GetAnchorPositionReflectsTabOrientation) {
+  TestingProfile profile;
+
+  testing::NiceMock<MockBrowserWindowInterface> mock_browser_window;
+  EXPECT_CALL(mock_browser_window, GetProfile())
+      .WillRepeatedly(testing::Return(&profile));
+  EXPECT_CALL(testing::Const(mock_browser_window), GetProfile())
+      .WillRepeatedly(testing::Return(&profile));
+  EXPECT_CALL(mock_browser_window, GetType())
+      .WillRepeatedly(
+          testing::Return(BrowserWindowInterface::Type::TYPE_NORMAL));
+
+  testing::NiceMock<MockTabSlotController> tab_slot_controller;
+  EXPECT_CALL(tab_slot_controller, GetBrowserWindowInterface())
+      .WillRepeatedly(testing::Return(&mock_browser_window));
+
+  BraveTab tab(tabs::TabHandle(1), &tab_slot_controller);
+
+  // Horizontal tabs: delegate to Tab::GetAnchorPosition() which returns
+  // TOP_LEFT.
+  profile.GetPrefs()->SetBoolean(brave_tabs::kVerticalTabsEnabled, false);
+  EXPECT_EQ(views::BubbleBorder::Arrow::TOP_LEFT, tab.GetAnchorPosition());
+
+  // Vertical tabs: must return LEFT_TOP so the hover card appears to the
+  // right of the tab strip for both the first hover (card creation) and
+  // subsequent hovers (card update via UpdateOrShowCard).
+  profile.GetPrefs()->SetBoolean(brave_tabs::kVerticalTabsEnabled, true);
+  EXPECT_EQ(views::BubbleBorder::Arrow::LEFT_TOP, tab.GetAnchorPosition());
+}