Fixing the dynamic positioning (move with anchor) for the app launcher

ash/wm/app_list_controller.cc

Index: ash/wm/app_list_controller.cc
diff --git a/ash/wm/app_list_controller.cc b/ash/wm/app_list_controller.cc
index ea5e4f4ce906b51952f53786cc45a77f1f97dc56..b04f4281a5488e19e109e09ae4af63fd3555aa51 100644
--- a/ash/wm/app_list_controller.cc
+++ b/ash/wm/app_list_controller.cc
@@ -39,11 +39,6 @@ const int kAnimationOffset = 8;
 // The maximum shift in pixels when over-scroll happens.
 const int kMaxOverScrollShift = 48;
 
-// The alternate shelf style adjusts the bubble to be flush with the shelf
-// when there is no bubble-tip. This is the tip height which needs to be
-// offsetted.
-const int kArrowTipHeight = 10;
-
 // The minimal anchor position offset to make sure that the bubble is still on
 // the screen with 8 pixels spacing on the left / right. This constant is a
 // result of minimal bubble arrow sizes and offsets.
@@ -88,9 +83,9 @@ gfx::Rect OffsetTowardsShelf(const gfx::Rect& rect, views::Widget* widget) {
   return offseted;
 }
 
-// Using |button_bounds|, determine the anchor so that the bubble gets shown
-// above the shelf (used for the alternate shelf theme).
-gfx::Point GetAdjustAnchorPositionToShelf(
+// Using |button_bounds|, determine the anchor offset so that the bubble gets
+// shown above the shelf (used for the alternate shelf theme).
+gfx::Point GetAnchorPositionOffsetToShelf(
     const gfx::Rect& button_bounds, views::Widget* widget) {
   DCHECK(Shell::HasInstance());
   ShelfAlignment shelf_alignment = Shell::GetInstance()->GetShelfAlignment(
@@ -102,24 +97,22 @@ gfx::Point GetAdjustAnchorPositionToShelf(
       {
         if (base::i18n::IsRTL()) {
           int screen_width = widget->GetWorkAreaBoundsInScreen().width();
-          anchor.set_x(std::min(screen_width - kMinimalAnchorPositionOffset,
-                                anchor.x()));
+          anchor.set_x(
+              std::min(screen_width - kMinimalAnchorPositionOffset - anchor.x(),
+                       0));
         } else {
-          anchor.set_x(std::max(kMinimalAnchorPositionOffset, anchor.x()));
+          anchor.set_x(std::max(kMinimalAnchorPositionOffset - anchor.x(), 0));
         }
-        int offset = button_bounds.height() / 2 - kArrowTipHeight;
-        if (shelf_alignment == SHELF_ALIGNMENT_TOP)
-          offset = -offset;
-        anchor.set_y(anchor.y() - offset);
+        anchor.set_y(0);
       }
       break;
     case SHELF_ALIGNMENT_LEFT:
-      anchor.set_x(button_bounds.right() - kArrowTipHeight);
-      anchor.set_y(std::max(kMinimalAnchorPositionOffset, anchor.y()));
+      anchor.set_x(0);
+      anchor.set_y(std::max(kMinimalAnchorPositionOffset - anchor.y(), 0));
       break;
     case SHELF_ALIGNMENT_RIGHT:
-      anchor.set_x(button_bounds.x() + kArrowTipHeight);
-      anchor.set_y(std::max(kMinimalAnchorPositionOffset, anchor.y()));
+      anchor.set_x(0);
+      anchor.set_y(std::max(kMinimalAnchorPositionOffset - anchor.y(), 0));
       break;
   }
 
@@ -173,18 +166,18 @@ void AppListController::SetVisible(bool visible, aura::Window* window) {
     if (ash::switches::UseAlternateShelfLayout()) {
       gfx::Rect applist_button_bounds = Launcher::ForWindow(container)->
           GetAppListButtonView()->GetBoundsInScreen();
-      view->InitAsBubble(
+      view->InitAsBubbleAttachedToAnchor(
           container,
           pagination_model_.get(),
-          NULL,
-          GetAdjustAnchorPositionToShelf(applist_button_bounds,
+          Launcher::ForWindow(container)->GetAppListButtonView(),
+          GetAnchorPositionOffsetToShelf(applist_button_bounds,
               Launcher::ForWindow(container)->GetAppListButtonView()->
                   GetWidget()),
           GetBubbleArrow(container),
           true /* border_accepts_events */);
       view->SetArrowPaintType(views::BubbleBorder::PAINT_NONE);
     } else {
-      view->InitAsBubble(
+      view->InitAsBubbleAttachedToAnchor(
           container,
           pagination_model_.get(),
           Launcher::ForWindow(container)->GetAppListButtonView(),