Remove manual Layout() from HoverButton

The only custom action in HoverButton's manual layout is to
position title label vertically in its parent. We create a small
custom view class for its parent to change its position upon bound
change. Therefore, we can remove the manual layout in HoverButton.

BUG=1005568

Change-Id: Iea0f9a8236a519373e299b31550d4240551cda7a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1866981
Commit-Queue: Wei Li <weili@chromium.org>
Reviewed-by: Allen Bauer <kylixrd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707575}

chrome/browser/ui/views/hover_button.cc

@@ -71,6 +71,27 @@ void SetTooltipAndAccessibleName(views::Button* parent,
 
 }  // namespace
 
+SingleLineStyledLabelWrapper::SingleLineStyledLabelWrapper(
+    const base::string16& title) {
+  auto title_label = std::make_unique<views::StyledLabel>(title, nullptr);
+  // Size without a maximum width to get a single line label.
+  title_label->SizeToFit(0);
+  label_ = AddChildView(std::move(title_label));
+}
+
+views::StyledLabel* SingleLineStyledLabelWrapper::label() {
+  return label_;
+}
+
+void SingleLineStyledLabelWrapper::OnBoundsChanged(
+    const gfx::Rect& previous_bounds) {
+  // Vertically center its child manually since it doesn't have a LayoutManager.
+  DCHECK(label_);
+
+  int y_center = (height() - label_->size().height()) / 2;
+  label_->SetPosition(gfx::Point(GetLocalBounds().x(), y_center));
+}
+
 HoverButton::HoverButton(views::ButtonListener* button_listener,
                          const base::string16& text)
     : views::LabelButton(/*button_listener*/ nullptr,
@@ -174,17 +195,8 @@ HoverButton::HoverButton(views::ButtonListener* button_listener,
                         row_height);
   icon_view_ = grid_layout->AddView(std::move(icon_view), 1, num_labels);
 
-  auto title_label = std::make_unique<views::StyledLabel>(title, nullptr);
-  // Size without a maximum width to get a single line label.
-  title_label->SizeToFit(0);
-  // |views::StyledLabel|s are all multi-line. With a layout manager,
-  // |StyledLabel| will try use the available space to size itself, and long
-  // titles will wrap to the next line (for smaller |HoverButton|s, this will
-  // also cover up |subtitle_|). Wrap it in a parent view with no layout manager
-  // to ensure it keeps its original size set by SizeToFit() above. Long titles
-  // will then be truncated.
-  auto title_wrapper = std::make_unique<views::View>();
-  title_ = title_wrapper->AddChildView(std::move(title_label));
+  auto title_wrapper = std::make_unique<SingleLineStyledLabelWrapper>(title);
+  title_ = title_wrapper->label();
   // Hover the whole button when hovering |title_|. This is OK because |title_|
   // will never have a link in it.
   title_wrapper->set_can_process_events_within_subtree(false);
@@ -315,17 +327,6 @@ std::unique_ptr<views::InkDrop> HoverButton::CreateInkDrop() {
   return ink_drop;
 }
 
-void HoverButton::Layout() {
-  LabelButton::Layout();
-
-  // Vertically center |title_| manually since it doesn't have a LayoutManager.
-  if (title_) {
-    DCHECK(title_->parent());
-    int y_center = title_->parent()->height() / 2 - title_->size().height() / 2;
-    title_->SetPosition(gfx::Point(title_->x(), y_center));
-  }
-}
-
 views::View* HoverButton::GetTooltipHandlerForPoint(const gfx::Point& point) {
   if (!HitTestPoint(point))
     return nullptr;

chrome/browser/ui/views/hover_button.h

@@ -30,6 +30,27 @@ class View;
 
 class PageInfoBubbleViewBrowserTest;
 
+// A special class used for wrapping a single line styled label.
+// |views::StyledLabel|s are all multi-line. With a layout manager,
+// |StyledLabel| will try use the available space to size itself, and long
+// titles will wrap to the next line (for smaller |HoverButton|s, this will
+// also cover up |subtitle_|). Wrap it in a parent view with no layout manager
+// to ensure it keeps its original size set by SizeToFit(). Long titles
+// will then be truncated.
+class SingleLineStyledLabelWrapper : public views::View {
+ public:
+  explicit SingleLineStyledLabelWrapper(const base::string16& title);
+  ~SingleLineStyledLabelWrapper() override = default;
+
+  // views::View
+  void OnBoundsChanged(const gfx::Rect& previous_bounds) override;
+
+  views::StyledLabel* label();
+
+ private:
+  views::StyledLabel* label_;
+};
+
 // A button taking the full width of its parent that shows a background color
 // when hovered over.
 // TODO (cyan): HoverButton should extend ButtonListener.
@@ -108,7 +129,6 @@ class HoverButton : public views::LabelButton,
   void StateChanged(ButtonState old_state) override;
   SkColor GetInkDropBaseColor() const override;
   std::unique_ptr<views::InkDrop> CreateInkDrop() override;
-  void Layout() override;
   views::View* GetTooltipHandlerForPoint(const gfx::Point& point) override;
   void OnBoundsChanged(const gfx::Rect& previous_bounds) override;