Change ToggleImageButton to be focusable by default

ToggleImageButton should exhibit similar behaviors as ImageButton:
focusable by default depending on the platform.

Bug: 1001103
Change-Id: I16f5fcf698b224864eac46e4c22ab57df7cb9641
Fixed: 1144611
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2513177Reviewed-by: Marijn Kruisselbrink <mek@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Wei Li <weili@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824207}

ash/system/holding_space/holding_space_item_view.cc

@@ -211,6 +211,7 @@ views::ToggleImageButton* HoldingSpaceItemView::AddPin(views::View* parent) {
   DCHECK(!pin_);
 
   pin_ = parent->AddChildView(std::make_unique<views::ToggleImageButton>());
+  pin_->SetFocusBehavior(views::View::FocusBehavior::ACCESSIBLE_ONLY);
   pin_->SetVisible(false);
 
   const SkColor icon_color = AshColorProvider::Get()->GetContentLayerColor(

chrome/browser/ui/views/native_file_system/native_file_system_usage_bubble_view.cc

@@ -39,7 +39,6 @@
 #include "ui/views/controls/scroll_view.h"
 #include "ui/views/controls/table/table_view.h"
 #include "ui/views/layout/box_layout.h"
-#include "ui/views/style/platform_style.h"
 
 namespace {
 
@@ -168,9 +167,6 @@ class CollapsibleListView : public views::View {
         l10n_util::GetStringUTF16(IDS_NATIVE_FILE_SYSTEM_USAGE_EXPAND));
     button->SetToggledTooltipText(
         l10n_util::GetStringUTF16(IDS_NATIVE_FILE_SYSTEM_USAGE_COLLAPSE));
-    // TODO(weili): remove this once ToggleImageButton has the default platform
-    // focus behavior.
-    button->SetFocusBehavior(views::PlatformStyle::DefaultFocusBehavior());
     expand_collapse_button_ = label_container->AddChildView(std::move(button));
     if (model->RowCount() < 3)
       expand_collapse_button_->SetVisible(false);

ui/views/controls/button/image_button.cc

@@ -218,7 +218,6 @@ const gfx::Point ImageButton::ComputeImagePaintPosition(
 
 ToggleImageButton::ToggleImageButton(PressedCallback callback)
     : ImageButton(std::move(callback)) {
-  SetFocusBehavior(FocusBehavior::ACCESSIBLE_ONLY);
 }
 
 ToggleImageButton::~ToggleImageButton() = default;