Align the base of the shelf's context menu to the top edge of the shelf.

ash/shelf/shelf_view.cc

Index: ash/shelf/shelf_view.cc
diff --git a/ash/shelf/shelf_view.cc b/ash/shelf/shelf_view.cc
index d2de17bb6a394191b941af37f8896dd32f8b07f3..4ce221b29ffb836818e22ea633efbf7172624f68 100644
--- a/ash/shelf/shelf_view.cc
+++ b/ash/shelf/shelf_view.cc
@@ -11,6 +11,7 @@
 #include "ash/drag_drop/drag_image_view.h"
 #include "ash/public/cpp/shelf_item_delegate.h"
 #include "ash/scoped_root_window_for_new_windows.h"
+#include "ash/screen_util.h"
 #include "ash/shelf/app_list_button.h"
 #include "ash/shelf/overflow_bubble.h"
 #include "ash/shelf/overflow_bubble_view.h"
@@ -1639,11 +1640,32 @@ void ShelfView::AfterItemSelected(
 void ShelfView::ShowContextMenuForView(views::View* source,
                                        const gfx::Point& point,
                                        ui::MenuSourceType source_type) {
+  // Align the context menu to the edge of the shelf.
+  aura::Window* shelf_window = shelf_widget_->GetNativeWindow();
+  gfx::Rect shelf_bounds =
+      is_overflow_mode()
+          ? (owner_overflow_bubble_->bubble_view()->GetBubbleBounds())

[msw, 2017/05/10 22:18:22]

nit: extra parens not needed here or on the next line.

[msw, 2017/05/11 17:13:39]

Just FYI, I would appreciate it if you respond to all comments, even if you just
use the 'Done' and 'Acknowledged' shortcut buttons. This helps me track how
comments have been addressed.

+          : (ScreenUtil::GetDisplayBoundsWithShelf(shelf_window));
+
+  gfx::Point context_menu_point;
+  switch (wm_shelf_->GetAlignment()) {
+    case SHELF_ALIGNMENT_BOTTOM:
+    case SHELF_ALIGNMENT_BOTTOM_LOCKED:
+      context_menu_point.SetPoint(point.x(),
+                                  shelf_bounds.bottom() - kShelfSize);
+      break;
+    case SHELF_ALIGNMENT_LEFT:
+      context_menu_point.SetPoint(shelf_bounds.x() + kShelfSize, point.y());
+      break;
+    case SHELF_ALIGNMENT_RIGHT:
+      context_menu_point.SetPoint(shelf_bounds.right() - kShelfSize, point.y());
+      break;
+  }
   last_pressed_index_ = -1;
 
   const ShelfItem* item = ShelfItemForView(source);
   if (!item) {
-    ShellPort::Get()->ShowContextMenu(point, source_type);
+    ShellPort::Get()->ShowContextMenu(context_menu_point, source_type);
     return;
   }
 
@@ -1653,8 +1675,8 @@ void ShelfView::ShowContextMenuForView(views::View* source,
     return;
 
   context_menu_id_ = item ? item->id : ShelfID();
-  ShowMenu(std::move(context_menu_model), source, point, true, source_type,
-           nullptr);
+  ShowMenu(std::move(context_menu_model), source, context_menu_point, true,
+           source_type, nullptr);
 }
 
 void ShelfView::ShowMenu(std::unique_ptr<ui::MenuModel> menu_model,
@@ -1671,7 +1693,8 @@ void ShelfView::ShowMenu(std::unique_ptr<ui::MenuModel> menu_model,
   closing_event_time_ = base::TimeTicks();
   int run_types = 0;
   if (context_menu)
-    run_types |= views::MenuRunner::CONTEXT_MENU;
+    run_types |=
+        views::MenuRunner::CONTEXT_MENU | views::MenuRunner::SHELF_CONTEXT_MENU;
   launcher_menu_runner_.reset(
       new views::MenuRunner(menu_model_adapter_->CreateMenu(), run_types));
 
@@ -1709,6 +1732,13 @@ void ShelfView::ShowMenu(std::unique_ptr<ui::MenuModel> menu_model,
     }
   }
 
+  // Distinguish the touch events that triggered on the bottom shelf or

[msw, 2017/05/10 22:18:22]

Should this be clobbering the |menu_alignment| values assigned in the |if
(!context_menu)| block above? If so, remove those assignments? (you should test
the application menu for items with multiple windows)

[minch1, 2017/05/11 16:34:02]

Oh, here will reassign the menu_alignment if |if(!context_menu)| happens, there
are different alignments. I think I should put following lines in |else| block
instead. 

[msw, 2017/05/11 17:13:39]

aside: it'd be nice if UX wanted both menus to look/act the same.

+  // left / right shelf. Since they should have different |MenuAnchorPosition|.
+  if (wm_shelf_->IsHorizontalAlignment())
+    menu_alignment = views::MENU_ANCHOR_FIXED_BOTTOMCENTER;
+  else
+    menu_alignment = views::MENU_ANCHOR_SIDECENTER;
+
   // NOTE: if you convert to HAS_MNEMONICS be sure to update menu building code.
   launcher_menu_runner_->RunMenuAt(source->GetWidget(), nullptr, anchor,
                                    menu_alignment, source_type);
@@ -1795,7 +1825,7 @@ bool ShelfView::CanPrepareForDrag(Pointer pointer,
     return false;
   }
 
-  // Touch dragging only begins after a dealy from the press event. This
+  // Touch dragging only begins after a delay from the press event. This
   // prevents accidental dragging on swipe or scroll gestures.
   if (pointer == TOUCH &&
       (base::TimeTicks::Now() - touch_press_time_) <