Get rid of Move Up / Down for 1 bookmark

Bug: 989787
Change-Id: I60b320350ccdd640f246d26af422f70b1d2a40b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733114Reviewed-by: Theresa  <twellington@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Jenna Himawan <jhimawan@google.com>
Cr-Commit-Position: refs/heads/master@{#683801}

chrome/android/java/src/org/chromium/chrome/browser/bookmarks/BookmarkRow.java

@@ -42,12 +42,13 @@ abstract class BookmarkRow extends SelectableItemView<BookmarkId>
     @Location
     private int mLocation;
 
-    @IntDef({Location.TOP, Location.MIDDLE, Location.BOTTOM})
+    @IntDef({Location.TOP, Location.MIDDLE, Location.BOTTOM, Location.SOLO})
     @Retention(RetentionPolicy.SOURCE)
     public @interface Location {
         int TOP = 0;
         int MIDDLE = 1;
         int BOTTOM = 2;
+        int SOLO = 3;
     }
 
     /**
@@ -153,11 +154,14 @@ abstract class BookmarkRow extends SelectableItemView<BookmarkId>
                         new Item(getContext(), R.string.bookmark_item_delete, true)));
         if (mReorderBookmarksEnabled
                 && mDelegate.getCurrentState() == BookmarkUIState.STATE_FOLDER) {
-            if (mLocation != Location.TOP) {
-                menuItems.add(new Item(getContext(), R.string.menu_item_move_up, true));
-            }
-            if (mLocation != Location.BOTTOM) {
-                menuItems.add(new Item(getContext(), R.string.menu_item_move_down, true));
+            // Only add move up / move down buttons if there is more than 1 item
+            if (mLocation != Location.SOLO) {
+                if (mLocation != Location.TOP) {
+                    menuItems.add(new Item(getContext(), R.string.menu_item_move_up, true));
+                }
+                if (mLocation != Location.BOTTOM) {
+                    menuItems.add(new Item(getContext(), R.string.menu_item_move_down, true));
+                }
             }
         }
         return menuItems.toArray(new Item[menuItems.size()]);

chrome/android/java/src/org/chromium/chrome/browser/bookmarks/ReorderBookmarkItemsAdapter.java

@@ -485,7 +485,9 @@ class ReorderBookmarkItemsAdapter extends DragReorderableListAdapter<BookmarkIte
     }
 
     private @Location int getLocationFromPosition(int position) {
-        if (position == getBookmarkItemStartIndex()) {
+        if (position == getBookmarkItemStartIndex() && position == getBookmarkItemEndIndex()) {
+            return Location.SOLO;
+        } else if (position == getBookmarkItemStartIndex()) {
             return Location.TOP;
         } else if (position == getBookmarkItemEndIndex()) {
             return Location.BOTTOM;

chrome/android/javatests/src/org/chromium/chrome/browser/bookmarks/BookmarkReorderTest.java

@@ -557,6 +557,23 @@ public class BookmarkReorderTest extends BookmarkTest {
         onView(withText("Move down")).check(doesNotExist());
     }
 
+    @Test
+    @MediumTest
+    public void testMoveButtonsGoneWithOneBookmark() throws Exception {
+        addFolder(TEST_FOLDER_TITLE);
+        BookmarkPromoHeader.forcePromoStateForTests(BookmarkPromoHeader.PromoState.PROMO_SYNC);
+        openBookmarkManager();
+
+        View testFolder = mItemsContainer.findViewHolderForAdapterPosition(1).itemView;
+        Assert.assertEquals("Wrong bookmark item selected.", TEST_FOLDER_TITLE,
+                ((BookmarkFolderRow) testFolder).getTitle());
+        View more = testFolder.findViewById(R.id.more);
+        TestThreadUtils.runOnUiThreadBlocking(more::callOnClick);
+
+        onView(withText("Move up")).check(doesNotExist());
+        onView(withText("Move down")).check(doesNotExist());
+    }
+
     @Override
     protected void openBookmarkManager() throws InterruptedException {
         super.openBookmarkManager();