Long-press on an app to reveal its shortcuts.

- Add ShortcutsContainerListener to icons on workspace, folders, and
  all apps. This handles long-press and forwards following touches to
  the DeepShortcutsContainer that is created.
- Drag over shortcut before lifting finger to launch it.
- Shortcuts are rendered in pill-shaped DeepShortcutViews,
  which are inside DeepShortcutContainer on DragLayer.
- The shortcut container orients above or below the icon, and left or
  right-aligns with it. Biases for above + left-align.
- Long press a DeepShortcutPill to drag and pin it to the workspace.

Bug: 28980830
Change-Id: I08658d13ae51fe53064644e8d8f7b42f150fdd7d

src/com/android/launcher3/Workspace.java

@@ -77,7 +77,8 @@ import com.android.launcher3.dragndrop.SpringLoadedDragController;
 import com.android.launcher3.folder.Folder;
 import com.android.launcher3.folder.FolderIcon;
 import com.android.launcher3.logging.UserEventDispatcher;
-import com.android.launcher3.pageindicators.PageIndicator;
+import com.android.launcher3.shortcuts.DeepShortcutManager;
+import com.android.launcher3.shortcuts.ShortcutsContainerListener;
 import com.android.launcher3.userevent.nano.LauncherLogProto;
 import com.android.launcher3.userevent.nano.LauncherLogProto.Target;
 import com.android.launcher3.util.LongArrayMap;
@@ -1094,6 +1095,10 @@ public class Workspace extends PagedView
         if (!(child instanceof Folder)) {
             child.setHapticFeedbackEnabled(false);
             child.setOnLongClickListener(mLongClickListener);
+            if (child instanceof BubbleTextView && DeepShortcutManager.supportsShortcuts(info)) {
+                // TODO: only add this listener if the item has shortcuts associated with it.
+                child.setOnTouchListener(new ShortcutsContainerListener((BubbleTextView) child));
+            }
         }
         if (child instanceof DropTarget) {
             mDragController.addDropTarget((DropTarget) child);