Fix contact picker list when switching to search.

We need to notify the recycler view that our list content has changed
when switching between search / non-search as the top item is the
(hidden) select all button if we're in non-search mode.

Bug: 985715,985711
Change-Id: Id1d8d18f8b71aea05f5ca1fb634ea54323ef6cfb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1724085Reviewed-by: Peter Beverloo <peter@chromium.org>
Commit-Queue: Richard Knoll <knollr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#681862}

chrome/android/java/src/org/chromium/chrome/browser/contacts_picker/PickerAdapter.java

@@ -132,6 +132,7 @@ public class PickerAdapter extends Adapter<RecyclerView.ViewHolder>
      */
     public void setSearchMode(boolean searchMode) {
         mSearchMode = searchMode;
+        notifyDataSetChanged();
     }
 
     /**