refactor: fix modernize-return-braced-init-list warnings (#44857)

* refactor: avoid repeating the return type from the declaration; use a braced initializer list instead [modernize-return-braced-init-list]

Co-authored-by: Charles Kerr <charles@charleskerr.com>

* refactor: avoid repeating the return type from the declaration; use a braced initializer list instead [modernize-return-braced-init-list]

NB: using the braced-initializer list uncovered an error here:
the float returned by std::floor() can't be implicitly cast to
an int. This is solved by using base::ClampFloor<int>() instead.
std::floor()

Co-authored-by: Charles Kerr <charles@charleskerr.com>

---------

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Charles Kerr <charles@charleskerr.com>

shell/browser/ui/autofill_popup.cc

@@ -245,7 +245,7 @@ gfx::Rect AutofillPopup::popup_bounds_in_view() {
   gfx::Point origin(popup_bounds_.origin());
   views::View::ConvertPointFromScreen(parent_, &origin);
 
-  return gfx::Rect(origin, popup_bounds_.size());
+  return {origin, popup_bounds_.size()};
 }
 
 void AutofillPopup::OnViewBoundsChanged(views::View* view) {
@@ -280,9 +280,8 @@ int AutofillPopup::GetDesiredPopupWidth() {
 gfx::Rect AutofillPopup::GetRowBounds(int index) {
   int top = kPopupBorderThickness + index * kRowHeight;
 
-  return gfx::Rect(kPopupBorderThickness, top,
-                   popup_bounds_.width() - 2 * kPopupBorderThickness,
-                   kRowHeight);
+  return {kPopupBorderThickness, top,
+          popup_bounds_.width() - 2 * kPopupBorderThickness, kRowHeight};
 }
 
 const gfx::FontList& AutofillPopup::GetValueFontListForRow(int index) const {

shell/browser/ui/electron_desktop_window_tree_host_linux.cc

@@ -50,12 +50,12 @@ gfx::Insets ElectronDesktopWindowTreeHostLinux::CalculateInsetsInDIP(
     ui::PlatformWindowState window_state) const {
   // If we are not showing frame, the insets should be zero.
   if (native_window_view_->IsFullscreen()) {
-    return gfx::Insets();
+    return {};
   }
 
   if (!native_window_view_->has_frame() ||
       !native_window_view_->has_client_frame()) {
-    return gfx::Insets();
+    return {};
   }
 
   auto* view = static_cast<ClientFrameViewLinux*>(

shell/browser/ui/tray_icon.cc

@@ -13,7 +13,7 @@ TrayIcon::TrayIcon() = default;
 TrayIcon::~TrayIcon() = default;
 
 gfx::Rect TrayIcon::GetBounds() {
-  return gfx::Rect();
+  return {};
 }
 
 void TrayIcon::NotifyClicked(const gfx::Rect& bounds,

shell/browser/ui/views/client_frame_view_linux.cc

@@ -154,8 +154,8 @@ gfx::Insets ClientFrameViewLinux::GetBorderDecorationInsets() const {
 }
 
 gfx::Insets ClientFrameViewLinux::GetInputInsets() const {
-  return gfx::Insets(
-      host_supports_client_frame_shadow_ ? -kResizeOutsideBorderSize : 0);
+  return gfx::Insets{
+      host_supports_client_frame_shadow_ ? -kResizeOutsideBorderSize : 0};
 }
 
 gfx::Rect ClientFrameViewLinux::GetWindowContentBounds() const {
@@ -457,7 +457,7 @@ void ClientFrameViewLinux::LayoutButtonsOnSide(
 
 gfx::Rect ClientFrameViewLinux::GetTitlebarBounds() const {
   if (frame_->IsFullscreen()) {
-    return gfx::Rect();
+    return {};
   }
 
   int font_height = gfx::FontList().GetHeight();

shell/browser/ui/views/opaque_frame_view.cc

@@ -338,7 +338,7 @@ bool OpaqueFrameView::IsFrameCondensed() const {
 }
 
 gfx::Insets OpaqueFrameView::RestoredFrameBorderInsets() const {
-  return gfx::Insets();
+  return {};
 }
 
 gfx::Insets OpaqueFrameView::RestoredFrameEdgeInsets() const {