Moving rearrangementExists to ReorderLogic since it's only used there

Also, simplify copyCurrentStateToSolution since it always gets false
as the second parameter.

Flag: NA
Bug: 229292911
Test: ReorderAlgorithmUnitTest
Change-Id: I025566897246fa59ca513cb7de9a12465054498f
diff --git a/src/com/android/launcher3/MultipageCellLayout.java b/src/com/android/launcher3/MultipageCellLayout.java
index 123e8ca..5c5d71c 100644
--- a/src/com/android/launcher3/MultipageCellLayout.java
+++ b/src/com/android/launcher3/MultipageCellLayout.java
@@ -120,7 +120,7 @@
     }
 
     @Override
-    public void copyCurrentStateToSolution(ItemConfiguration solution, boolean temp) {
+    public void copyCurrentStateToSolution(ItemConfiguration solution) {
         int childCount = mShortcutsAndWidgets.getChildCount();
         for (int i = 0; i < childCount; i++) {
             View child = mShortcutsAndWidgets.getChildAt(i);