964285 - "blank" tiles under about:start shouldn't be selectable

Status: VERIFIED FIXED

(Firefox for Metro Graveyard :: Browser, defect, P2)

Description

[Kamil Jozwiak [:kjozwiak]]

Attachment: Blank tiles selected and difficult to clear selection

When you swipe and select a "blank" tile from the about:screen, the "Selection App Bar" will not slide into view making it very difficult to unselect them after. I tried selecting several valid tiles and then taping on "clear selection", but the selected "blank" tiles didn't clear. I had to press "F5" to refresh the entire screen and deselect everything.

- I've attached a screenshot to illustrate the issue

Steps to reproduce the issue:

1) Open Firefox Metro
2) Under the about:start screen, select several "blank" tiles by using the swipe gesture (up/downs swipe)
3) You'll notice that once the tiles are selected, it's really difficult to clear them unless you refresh the entire page

Current Behavior:

- If the user selects "blank" tiles from the about:start screen, they can't clear it through the "Selection App Bar"

Expected Behavior:

- I don't think the user's should be able to select tiles if they are completely blank. If the changes are to difficult, we should at least let the users clear the selections.

Found the issue using the following builds:
- http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014-01-26-00-40-02-mozilla-aurora/
- http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014-01-26-03-02-03-mozilla-central/

Comment 1

[Rodrigo Silveira [:rsilveira] [:rodms]]

Yeah, we shouldn't allow selection of blank tiles. You can't select them with mouse, only with touch.

Comment 2

[Sam Foster [:sfoster] (he/him)]

Attachment: Guard against selecting non-item elements

I've replaced a few ad-hock checks with an isItem validation method on richgrid, and a similar sanity check in CrossSlide.jsm. New tests that pass - as do the existing ones. 
If this is nervous-making, we could possibly break out the CrossSlide.jsm change to make a lower-risk fix for uplift?

Comment 3

[Sam Foster [:sfoster] (he/him)]

On fx-team:  https://hg.mozilla.org/integration/fx-team/rev/a09caf2b867f

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/a09caf2b867f

Comment 5

[Cornel Ionce [:noni] [Hubs QA]]

Mozilla/5.0 (Windows NT 6.3; WOW64; rv:29.0) Gecko/20100101 Firefox/29.0

Vetified as fixed with a Surface Pro 2 device on latest Aurora (build ID: 20140206004003) using the STR from the description.