Animating docked background in sync with shelf

ash/shelf/shelf_widget.cc

Index: ash/shelf/shelf_widget.cc
diff --git a/ash/shelf/shelf_widget.cc b/ash/shelf/shelf_widget.cc
index 8dc737ab542a732fc0d6b0bb960921e0854449a8..a4de02568014d0cd8d18e6c3232d2b82513d661b 100644
--- a/ash/shelf/shelf_widget.cc
+++ b/ash/shelf/shelf_widget.cc
@@ -46,7 +46,6 @@ const int kDimAlpha = 128;
 // The time to dim and un-dim.
 const int kTimeToDimMs = 3000;  // Slow in dimming.
 const int kTimeToUnDimMs = 200;  // Fast in activating.
-const int kTimeToSwitchBackgroundMs = 1000;
 
 // Class used to slightly dim shelf items when maximized and visible.
 class DimmerView : public views::View,
@@ -145,7 +144,7 @@ DimmerView::DimmerView(ash::ShelfWidget* shelf_widget,
   // Make sure it is undimmed at the beginning and then fire off the dimming
   // animation.
   background_animator_.SetPaintsBackground(false,
-      ash::internal::BackgroundAnimator::CHANGE_IMMEDIATE);
+                                           ash::BACKGROUND_CHANGE_IMMEDIATE);
   SetHovered(false);
 }
 
@@ -161,8 +160,7 @@ void DimmerView::SetHovered(bool hovered) {
   background_animator_.SetDuration(hovered ? kTimeToUnDimMs : kTimeToDimMs);
   background_animator_.SetPaintsBackground(!hovered,
       disable_dimming_animations_for_test_ ?
-          ash::internal::BackgroundAnimator::CHANGE_IMMEDIATE :
-          ash::internal::BackgroundAnimator::CHANGE_ANIMATE);
+          ash::BACKGROUND_CHANGE_IMMEDIATE : ash::BACKGROUND_CHANGE_ANIMATE);
 }
 
 void DimmerView::ForceUndimming(bool force) {
@@ -391,22 +389,55 @@ void ShelfWidget::DelegateView::OnPaintBackground(gfx::Canvas* canvas) {
             SkBitmapOperations::ROTATION_90_CW,
             SkBitmapOperations::ROTATION_270_CW,
             SkBitmapOperations::ROTATION_180_CW));
-
-  gfx::Rect black_rect =
-      shelf_->shelf_layout_manager()->SelectValueForShelfAlignment(
-          gfx::Rect(0, height() - kNumBlackPixels, width(), kNumBlackPixels),
-          gfx::Rect(0, 0, kNumBlackPixels, height()),
-          gfx::Rect(width() - kNumBlackPixels, 0, kNumBlackPixels, height()),
-          gfx::Rect(0, 0, width(), kNumBlackPixels));
-
+  const gfx::Rect dock_bounds(shelf_->shelf_layout_manager()->dock_bounds());
   SkPaint paint;
   paint.setAlpha(alpha_);
   canvas->DrawImageInt(
       launcher_background,
       0, 0, launcher_background.width(), launcher_background.height(),
-      0, 0, width(), height(),
+      (SHELF_ALIGNMENT_BOTTOM == shelf_->GetAlignment() &&
+       dock_bounds.x() == 0 && dock_bounds.width() > 0) ?
+           dock_bounds.width() : 0, 0,
+      SHELF_ALIGNMENT_BOTTOM == shelf_->GetAlignment() ?
+          width() - dock_bounds.width() : width(), height(),
       false,
       paint);
+  if (SHELF_ALIGNMENT_BOTTOM == shelf_->GetAlignment() &&
+      dock_bounds.width() > 0) {
+    // The part of the shelf background that is in the corner below the docked
+    // windows close to the work area is an arched gradient that blends
+    // vertically oriented docked background and horizontal shelf.
+    gfx::ImageSkia launcher_corner =
+        *rb.GetImageSkiaNamed(IDR_AURA_LAUNCHER_CORNER);
+    if (dock_bounds.x() == 0) {
+      launcher_corner = gfx::ImageSkiaOperations::CreateRotatedImage(
+          launcher_corner, SkBitmapOperations::ROTATION_90_CW);
+    }
+    canvas->DrawImageInt(
+        launcher_corner,
+        0, 0, launcher_corner.width(), launcher_corner.height(),
+        dock_bounds.x() > 0 ? dock_bounds.x() : dock_bounds.width() - height(),
+        0,
+        height(), height(),
+        false,
+        paint);
+    // The part of the shelf background that is just below the docked windows
+    // is drawn using the last (lowest) 1-pixel tall strip of the image asset.
+    // This avoids showing the border 3D shadow between the shelf and the dock.
+    canvas->DrawImageInt(
+        launcher_background,
+        0, launcher_background.height() - 1, launcher_background.width(), 1,
+        dock_bounds.x() > 0 ? dock_bounds.x() + height() : 0, 0,
+        dock_bounds.width() - height(), height(),
+        false,
+        paint);
+  }
+  gfx::Rect black_rect =
+      shelf_->shelf_layout_manager()->SelectValueForShelfAlignment(
+          gfx::Rect(0, height() - kNumBlackPixels, width(), kNumBlackPixels),
+          gfx::Rect(0, 0, kNumBlackPixels, height()),
+          gfx::Rect(width() - kNumBlackPixels, 0, kNumBlackPixels, height()),
+          gfx::Rect(0, 0, width(), kNumBlackPixels));
   canvas->FillRect(black_rect, SK_ColorBLACK);
 }
 
@@ -521,12 +552,12 @@ ShelfWidget::~ShelfWidget() {
 
 void ShelfWidget::SetPaintsBackground(
     ShelfBackgroundType background_type,
-    internal::BackgroundAnimator::ChangeType change_type) {
+    BackgroundAnimatorChangeType change_type) {
   ui::Layer* opaque_background = delegate_view_->opaque_background();
   float target_opacity =
       (background_type == SHELF_BACKGROUND_MAXIMIZED) ? 1.0f : 0.0f;
   scoped_ptr<ui::ScopedLayerAnimationSettings> opaque_background_animation;
-  if (change_type != internal::BackgroundAnimator::CHANGE_IMMEDIATE) {
+  if (change_type != BACKGROUND_CHANGE_IMMEDIATE) {
     opaque_background_animation.reset(new ui::ScopedLayerAnimationSettings(
         opaque_background->GetAnimator()));
     opaque_background_animation->SetTransitionDuration(
@@ -536,9 +567,11 @@ void ShelfWidget::SetPaintsBackground(
 
   // TODO(mukai): use ui::Layer on both opaque_background and normal background
   // retire background_animator_ at all. It would be simpler.
+  // See also DockedBackgroundWidget::SetPaintsBackground.
   background_animator_.SetPaintsBackground(
       background_type != SHELF_BACKGROUND_DEFAULT,
       change_type);
+  delegate_view_->SchedulePaint();
 }
 
 ShelfBackgroundType ShelfWidget::GetBackgroundType() const {