Update drag and drop visualizations

=> Remove the bitmap-based icon outline
=> Add simple cell based location preview of drop location
=> Round corners of page outlines
=> Get rid of page background for focused page
=> Update colors to use system accent color

Bug: 185163323

Test: manual

Change-Id: Id604c59201536967e25236f305eeeb0aafc9c022

src/com/android/launcher3/dragndrop/DragLayer.java

diff --git a/src/com/android/launcher3/dragndrop/DragLayer.java b/src/com/android/launcher3/dragndrop/DragLayer.java
index c80fd90..274e033 100644
--- a/src/com/android/launcher3/dragndrop/DragLayer.java
+++ b/src/com/android/launcher3/dragndrop/DragLayer.java
@@ -46,8 +46,8 @@
 import com.android.launcher3.ShortcutAndWidgetContainer;
 import com.android.launcher3.Workspace;
 import com.android.launcher3.folder.Folder;
+import com.android.launcher3.graphics.Scrim;
 import com.android.launcher3.graphics.SysUiScrim;
-import com.android.launcher3.graphics.WorkspaceDragScrim;
 import com.android.launcher3.keyboard.ViewGroupFocusHelper;
 import com.android.launcher3.util.Thunk;
 import com.android.launcher3.views.BaseDragLayer;
@@ -83,7 +83,7 @@
 
     // Related to adjacent page hints
     private final ViewGroupFocusHelper mFocusIndicatorHelper;
-    private WorkspaceDragScrim mWorkspaceDragScrim;
+    private Scrim mWorkspaceDragScrim;
     private SysUiScrim mSysUiScrim;
     private LauncherRootView mRootView;
 
@@ -106,9 +106,7 @@
     public void setup(DragController dragController, Workspace workspace) {
         mDragController = dragController;
         recreateControllers();
-
-        mWorkspaceDragScrim = new WorkspaceDragScrim((this));
-        mWorkspaceDragScrim.setWorkspace(workspace);
+        mWorkspaceDragScrim = new Scrim(this);
 
         // We delegate drawing of the workspace scrim to LauncherRootView (one level up), so as
         // to avoid artifacts when translating the entire drag layer in the -1 transition.
@@ -540,7 +538,7 @@
         mSysUiScrim.onInsetsChanged(insets, mAllowSysuiScrims);
     }
 
-    public WorkspaceDragScrim getWorkspaceDragScrim() {
+    public Scrim getWorkspaceDragScrim() {
         return mWorkspaceDragScrim;
     }