Adds functionality to anchor widgets to the top-of-window views in immersive mode

chrome/browser/ui/views/frame/top_container_view.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/ui/views/frame/top_container_view.h"
 
 #include "chrome/browser/ui/views/frame/browser_frame.h"
 #include "chrome/browser/ui/views/frame/browser_view.h"
 #include "chrome/browser/ui/views/frame/immersive_mode_controller.h"
 
 TopContainerView::TopContainerView(BrowserView* browser_view)
     : browser_view_(browser_view) {
 }
 
 TopContainerView::~TopContainerView() {
 }
 
+gfx::Rect TopContainerView::GetTargetBoundsInScreen() const {
+  if (!parent())
+    return bounds();
+
+  // Compute transform relative to parent.
+  gfx::Transform transform;
+  if (layer())
+    transform = layer()->GetTargetTransform();
+  gfx::Transform translation;
+  translation.Translate(static_cast<float>(GetMirroredX()),
+                        static_cast<float>(y()));
+  transform.ConcatTransform(translation);
+
+  gfx::Point origin(parent()->GetBoundsInScreen().origin());
+  transform.TransformPoint(origin);
+  return gfx::Rect(origin, size());
+}
+
 gfx::Size TopContainerView::GetPreferredSize() {
   // The view wants to be as wide as its parent and tall enough to fully show
   // its last child view.
   int last_child_bottom =
       child_count() > 0 ? child_at(child_count() - 1)->bounds().bottom() : 0;
   return gfx::Size(browser_view_->width(), last_child_bottom);
 }
 
 std::string TopContainerView::GetClassName() const {
   return "TopContainerView";
 }
 
+void TopContainerView::OnBoundsChanged(const gfx::Rect& previous_bounds) {
+  ImmersiveModeController* immersive_controller =
+      browser_view_->immersive_mode_controller();
+  if (immersive_controller->IsEnabled())
+    immersive_controller->OnTopContainerBoundsChanged();
+}
+
 void TopContainerView::PaintChildren(gfx::Canvas* canvas) {
   if (browser_view_->immersive_mode_controller()->IsRevealed()) {
     // Top-views depend on parts of the frame (themes, window buttons) being
     // painted underneath them. Clip rect has already been set to the bounds
     // of this view, so just paint the frame.
     views::View* frame = browser_view_->frame()->GetFrameView();
     frame->Paint(canvas);
   }
 
   views::View::PaintChildren(canvas);
 }