commit eb64e7a49d6cf73b3fb07c88449f8cc03e3e4d6b
author Samuel Huang <huangs@chromium.org> Wed Jul 23 19:39:27 2025
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Jul 23 19:39:27 2025
tree 651e34bf0a21f5c6d4554d1d5aa8d59aab033007
parent 2af176b4bf5ba73755ea71a1a48a573b928bd4d1

[MVT Customization] Make "divider gap" same as "tile gap".

MVTs consist of Custom Tiles (CTs) and Top Sites Tiles (TSTs). The
divider is found between the last CT and the first TST. Let "tile gap"
be the common icon distance between adjacent CTs and adjacent TSTs. Let
"divider gap" be the icon distance between the last CT and the first
TST (across the divider).

"Tile gap" arises from each tile's internal spacing and assigned
"internal margin", which is applied (as start margin) to all but the
first tile in TilesLinearLayout.setIntervalMargins().

For uniformity, the divider was given the same "internal margin". We
then chose divider width (R.dimen.tile_view_divider_width = 8bp) to fit
the UI mock. As a result, the "divider gap" is larger than "tile gap" --
but this looks great when the divider is always present.

In crrev.com/c/6774848 we hide the divider hidden by default, and only
show it briefly with animation (adjusts alpha) on CT update. But without
the divider, the "divider gap" is noticeably bigger than "tile gap",
especially in landscape mode!

This CL fixes the issue by making "divider gap" same as "tile gap". The
trade-off is that when the divider is shown it looks a bit cramped --
but this is fine since the divider is transient anyway.

Details:
* TileLinearLayout: Make updateView{Start,End}Margin() protected.
* MostVisitedTilesLayout:
  * Cache `mTileViewDividerWidth`.
    * The divider width is now arbitrary -- but we keep it anyway.
  * Store `mDividerIndex` along with `mTileViewDividerWidth`.
  * Override setIntervalMargins(): If the divider is present, calculate
    adjusted margin, and assign it as the start margin to the divider
    and its next sibling.

Bug: 433272602, 388782412
Change-Id: I1d00be64b20d0b9f6a4f857d7b439fa615b28d71
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6780677
Reviewed-by: Calder Kitagawa <ckitagawa@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1491033}