Adding animation so the CellLayout is properly spaced on Foldables

Flag: LEGACY FOLDABLE_SINGLE_PAGE DISABLED
Fix: 294841331
Test: atest HomeScreenEditStateImageTest
Change-Id: I5dc94b63ca322748b952ce4bd55b6951d51d190f

src/com/android/launcher3/CellLayout.java

@@ -57,6 +57,7 @@ import android.view.ViewGroup;
 import android.view.accessibility.AccessibilityEvent;
 
 import androidx.annotation.IntDef;
+import androidx.annotation.Px;
 import androidx.core.graphics.ColorUtils;
 import androidx.core.view.ViewCompat;
 
@@ -175,6 +176,8 @@ public class CellLayout extends ViewGroup {
 
     private final TimeInterpolator mEaseOutInterpolator;
     protected final ShortcutAndWidgetContainer mShortcutsAndWidgets;
+    @Px
+    protected int mSpaceBetweenCellLayoutsPx = 0;
 
     @Retention(RetentionPolicy.SOURCE)
     @IntDef({WORKSPACE, HOTSEAT, FOLDER})
@@ -636,12 +639,19 @@ public class CellLayout extends ViewGroup {
                 mVisualizeGridPaint.setColor(Color.argb((int) (alpha),
                         Color.red(mGridColor), Color.green(mGridColor), Color.blue(mGridColor)));
 
+                canvas.save();
+                canvas.translate(getMarginForGivenCellParams(params), 0);
                 canvas.drawRoundRect(mVisualizeGridRect, mGridVisualizationRoundingRadius,
                         mGridVisualizationRoundingRadius, mVisualizeGridPaint);
+                canvas.restore();
             }
         }
     }
 
+    protected float getMarginForGivenCellParams(CellLayoutLayoutParams params) {
+        return 0;
+    }
+
     @Override
     protected void dispatchDraw(Canvas canvas) {
         super.dispatchDraw(canvas);
@@ -2844,4 +2854,8 @@ public class CellLayout extends ViewGroup {
     public boolean isRegionVacant(int x, int y, int spanX, int spanY) {
         return mOccupied.isRegionVacant(x, y, spanX, spanY);
     }
+
+    public void setSpaceBetweenCellLayoutsPx(@Px int spaceBetweenCellLayoutsPx) {
+        mSpaceBetweenCellLayoutsPx = spaceBetweenCellLayoutsPx;
+    }
 }