Introduce AccessibilityFocusRing.

chrome/browser/chromeos/ui/focus_ring_layer.cc

 // Copyright 2013 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 "chrome/browser/chromeos/ui/focus_ring_layer.h"
 
 #include "base/bind.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
 #include "ui/gfx/canvas.h"
 
 namespace chromeos {
 
 namespace {
 
 const int kShadowRadius = 10;
 const int kShadowAlpha = 90;
 const SkColor kShadowColor = SkColorSetRGB(77, 144, 254);
 
 }  // namespace
 
 FocusRingLayerDelegate::~FocusRingLayerDelegate() {}
 
 FocusRingLayer::FocusRingLayer(FocusRingLayerDelegate* delegate)
-    : delegate_(delegate),
-      root_window_(NULL) {
+    : root_window_(NULL),
+      delegate_(delegate) {
 }
 
 FocusRingLayer::~FocusRingLayer() {}
 
 void FocusRingLayer::Set(aura::Window* root_window, const gfx::Rect& bounds) {
   focus_ring_ = bounds;
+  CreateOrUpdateLayer(root_window, "FocusRing");
+
+  // Update the layer bounds.
+  gfx::Rect layer_bounds = bounds;
+  int inset = -(kShadowRadius + 2);
+  layer_bounds.Inset(inset, inset, inset, inset);
+  layer_->SetBounds(layer_bounds);
+}
+
+void FocusRingLayer::CreateOrUpdateLayer(
+    aura::Window* root_window, const char* layer_name) {
   if (!layer_ || root_window != root_window_) {
     root_window_ = root_window;
     ui::Layer* root_layer = root_window->layer();
     layer_.reset(new ui::Layer(ui::LAYER_TEXTURED));
-    layer_->set_name("FocusRing");
+    layer_->set_name(layer_name);
     layer_->set_delegate(this);
     layer_->SetFillsBoundsOpaquely(false);
     root_layer->Add(layer_.get());
   }
 
   // Keep moving it to the top in case new layers have been added
   // since we created this layer.
   layer_->parent()->StackAtTop(layer_.get());
-
-  // Update the layer bounds.
-  gfx::Rect layer_bounds = bounds;
-  int inset = -(kShadowRadius + 2);
-  layer_bounds.Inset(inset, inset, inset, inset);
-  layer_->SetBounds(layer_bounds);
 }
 
 void FocusRingLayer::OnPaintLayer(gfx::Canvas* canvas) {
   if (!root_window_ || focus_ring_.IsEmpty())
     return;
 
   gfx::Rect bounds = focus_ring_ - layer_->bounds().OffsetFromOrigin();
   SkPaint paint;
   paint.setColor(kShadowColor);
   paint.setFlags(SkPaint::kAntiAlias_Flag);
@@ skipping 16 matching lines @@
 void FocusRingLayer::OnDeviceScaleFactorChanged(float device_scale_factor) {
   if (delegate_)
     delegate_->OnDeviceScaleFactorChanged();
 }
 
 base::Closure FocusRingLayer::PrepareForLayerBoundsChange() {
   return base::Bind(&base::DoNothing);
 }
 
 }  // namespace chromeos