Bottom browser controls position based on window height

chrome/browser/android/compositor/layer/toolbar_layer.cc

 // Copyright 2014 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/android/compositor/layer/toolbar_layer.h"
 
 #include "cc/layers/nine_patch_layer.h"
 #include "cc/layers/solid_color_layer.h"
 #include "cc/layers/ui_resource_layer.h"
 #include "cc/resources/scoped_ui_resource.h"
@@ skipping 13 matching lines @@
   return layer_;
 }
 
 void ToolbarLayer::PushResource(
     int toolbar_resource_id,
     int toolbar_background_color,
     bool anonymize,
     int toolbar_textbox_background_color,
     int url_bar_background_resource_id,
     float url_bar_alpha,
-    float view_height,
+    float window_height,
+    float y_offset,
     bool show_debug,
     bool clip_shadow,
     bool browser_controls_at_bottom) {
   ui::ResourceManager::Resource* resource =
       resource_manager_->GetResource(ui::ANDROID_RESOURCE_TYPE_DYNAMIC,
                                      toolbar_resource_id);
 
   // Ensure the toolbar resource is available before making the layer visible.
   layer_->SetHideLayerAndSubtree(!resource);
   if (!resource)
     return;
 
   // This layer effectively draws over the space it takes for shadows.  Set the
   // bounds to the non-shadow size so that other things can properly line up.
   // Padding height does not include the height of the tabstrip, so we add
   // it explicitly by adding y offset.
   gfx::Size size = gfx::Size(
       resource->padding.width(),
       resource->padding.height() + resource->padding.y());
   layer_->SetBounds(size);
 
   // The toolbar_root_ contains all of the layers that make up the toolbar. The
   // toolbar_root_ is moved around inside of layer_ to allow appropriate
   // clipping of the shadow.
   toolbar_root_->SetBounds(resource->padding.size());
 
+  gfx::PointF root_layer_position(0, y_offset);
   gfx::PointF background_position(resource->padding.origin());
   if (browser_controls_at_bottom) {
+    // The toolbar's position as if it were completely shown.
+    float base_toolbar_y = window_height - resource->padding.size().height();
     float layer_offset =
         resource->size.height() - resource->padding.size().height();
-    layer_->SetPosition(gfx::PointF(0, view_height));
+
+    root_layer_position.set_y(base_toolbar_y + y_offset);
     toolbar_root_->SetPosition(gfx::PointF(0, -layer_offset));
     background_position.set_y(layer_offset);
   }
+  layer_->SetPosition(root_layer_position);
 
   toolbar_background_layer_->SetBounds(resource->padding.size());
   toolbar_background_layer_->SetPosition(background_position);
   toolbar_background_layer_->SetBackgroundColor(toolbar_background_color);
 
   bool url_bar_visible = (resource->aperture.width() != 0);
   url_bar_background_layer_->SetHideLayerAndSubtree(!url_bar_visible);
   if (url_bar_visible) {
     ui::ResourceManager::Resource* url_bar_background_resource =
         resource_manager_->GetResource(ui::ANDROID_RESOURCE_TYPE_STATIC,
@@ skipping 110 matching lines @@
 
   debug_layer_->SetIsDrawable(true);
   debug_layer_->SetBackgroundColor(SK_ColorGREEN);
   debug_layer_->SetOpacity(0.5f);
 }
 
 ToolbarLayer::~ToolbarLayer() {
 }
 
 }  //  namespace android