Fix UI bugs for widget picker search.

- Mirror search icon in RTL (b/184162989)
- Fix spacing between edit text and cancel button, to make it consistent
with space between search icon and edit text. (b/183602001)
- Scroll to top on every search result. (b/183602001)
- Fix keyboard overlap on orientation change. This is fixed by clearing
text on edit text differently (b/184048899)

Test: Manually tested
Bug: 184162989
Bug: 183602001
Bug: 184048899
Change-Id: I72ed51e1968a55a3105bd8b389d1bbd74d50d8af
diff --git a/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java b/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
index a4257a2..f6ff87b 100644
--- a/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
+++ b/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
@@ -392,6 +392,7 @@
         mAdapters.get(AdapterHolder.SEARCH).mWidgetsListAdapter.setWidgetsOnSearch(entries);
         updateNoSearchResultsView(
                 mAdapters.get(AdapterHolder.SEARCH).mWidgetsListAdapter.getItemCount() == 0);
+        mAdapters.get(AdapterHolder.SEARCH).mWidgetsRecyclerView.scrollToTop();
     }
 
     private void setViewVisibilityBasedOnSearch(boolean isInSearchMode) {