Ensure that the focus ring in the bookmarks bar does not paint outside the parent view.

ui/views/controls/focus_ring.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/focus_ring.h"
 
 #include "ui/gfx/canvas.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/views/controls/focusable_border.h"
 
@@ skipping 22 matching lines @@
 
 const char FocusRing::kViewClassName[] = "FocusRing";
 
 // static
 views::View* FocusRing::Install(views::View* parent,
                                 ui::NativeTheme::ColorId override_color_id) {
   FocusRing* ring = GetFocusRing(parent);
   if (!ring) {
     ring = new FocusRing();
     parent->AddChildView(ring);
+    // A layer is necessary to paint beyond the parent's bounds.
+    ring->SetPaintToLayer();
+    ring->layer()->SetFillsBoundsOpaquely(false);
   }
   ring->override_color_id_ = override_color_id;
   ring->Layout();
   ring->SchedulePaint();
   return ring;
 }
 
 // static
 void FocusRing::Uninstall(views::View* parent) {
   delete GetFocusRing(parent);
@@ skipping 26 matching lines @@
                   0x66));
   flags.setStyle(cc::PaintFlags::kStroke_Style);
   flags.setStrokeWidth(kFocusHaloThicknessDp);
   gfx::RectF rect(GetLocalBounds());
   rect.Inset(gfx::InsetsF(kFocusHaloThicknessDp / 2.f));
   canvas->DrawRoundRect(rect, kFocusHaloCornerRadiusDp, flags);
 }
 
 FocusRing::FocusRing()
     : override_color_id_(ui::NativeTheme::kColorId_NumColors) {
-  // A layer is necessary to paint beyond the parent's bounds.
-  SetPaintToLayer();

[ananta, 2017/04/12 23:54:04]

Moved this code to FocusRing::Install() as we need the parent to be setup on the
view for the ChildLayerAdded() notification to be propagated up the parent
chain.

-  layer()->SetFillsBoundsOpaquely(false);
 }
 
 FocusRing::~FocusRing() {}
 
 }  // namespace views