Enabling accessible drag and drop

-> Using the context menu, and a new two stage system, this allows
   users to curate icons and widgets on the workspace
-> Move icons / widgets to any empty cell on any existing screen, or
   create a new screen (appended to the right, as with regular drag
   and drop)
-> Move icons into existing folders
-> Create folders by moving an icon onto another icon
-> Also added confirmations for these and some existing accessibility actions

Limitations:
-> Currently, no support for drag and drop in folders
-> Considering moving the drag view so it doesn't occlude any
   content (in particular, when user changes pages)
-> In this mode, accessibility framework seems to have
   problems with the next / prev operations

Bug: 18482913

Change-Id: I19b0be9dc8bfa766d430408c8ad9303c716b89b2
diff --git a/src/com/android/launcher3/LauncherAppState.java b/src/com/android/launcher3/LauncherAppState.java
index 8e6557f..d8896cc 100644
--- a/src/com/android/launcher3/LauncherAppState.java
+++ b/src/com/android/launcher3/LauncherAppState.java
@@ -62,7 +62,7 @@
     private static LauncherAppState INSTANCE;
 
     private DynamicGrid mDynamicGrid;
-    private AccessibilityDelegate mAccessibilityDelegate;
+    private LauncherAccessibilityDelegate mAccessibilityDelegate;
 
     public static LauncherAppState getInstance() {
         if (INSTANCE == null) {
@@ -168,7 +168,7 @@
         return mModel;
     }
 
-    AccessibilityDelegate getAccessibilityDelegate() {
+    LauncherAccessibilityDelegate getAccessibilityDelegate() {
         return mAccessibilityDelegate;
     }