GitLab

This CL fixes a couple issues on counting tile impressions on NTP.
1. NTP calls TileManager::GetTiles() to get both the top and sub tiles.
While Omnibox makes two separate calls of GetTiles() and
GetTile(). This CL fixes the behavior of NTP to match that of Omnibox, so we can
count top level tile impression when
GetTiles() is called, and counts subtile impression when GetTile()
is called.

2. Clicking the home button will often invoke 2 calls to GetTiles(). One
caused by QueryTileSection ctor, one caused by OnLoadUrl() for NTP.
We don't actually need to reload tiles if user never clicked on any
tiles. In most cases, only the call from ctor is necessary. This CL
fixes the issue by checking whether tiles has been clicked before
reloading all tiles.

BUG=1155919

Change-Id: Ief1f4be957d160119c40fec1da71ae79d6258321
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2576504
Commit-Queue: Min Qin <qinmin@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836218}