Query Tiles : Initial patch for NTP

This CL :
1 - Creates feature and flag for query tiles
2 - Adds java interface for query tiles service
3 - Initialized query tiles section in NTP
4 - Added factory and bridge for TileProvider

Bug: 1059409
Change-Id: I0f19ad10b233e15b24b7b32073ffaa9794f7181a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2092204
Commit-Queue: Shakti Sahu <[email protected]>
Reviewed-by: David Trainor <[email protected]>
Cr-Commit-Position: refs/heads/master@{#749531}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 6022562..61373f5 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -1443,6 +1443,9 @@
 extern const char kProcessSharingWithStrictSiteInstancesName[];
 extern const char kProcessSharingWithStrictSiteInstancesDescription[];
 
+extern const char kQueryTilesName[];
+extern const char kQueryTilesDescription[];
+
 extern const char kReaderModeHeuristicsName[];
 extern const char kReaderModeHeuristicsDescription[];
 extern const char kReaderModeHeuristicsMarkup[];