Smol fixes batch 1

[Kiki79250CoC]

This is a mini-collection of small fixes I've done, in an attempt to correct some issues that happens with Geckium.

I want to note that I did the tests in a rustic way, as I "simulated" the compiler myself (yes) to see if it works. In my tests it does, but I'm probably sure it isn't.

1. Fix Dropdown menus

Commits 7d7d8f5, 65fe941

This attempts to fix the dropdown lists text color on selected items, and the arrow as well
This fix is probably not done the best way, but at least it seems to work.

Before	After

2. Fix the "No update available" text on Add-ons page

Commits 7feda0a, 9a3f721

It just moves the text to not be covered by the search box.

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3. Fix the search box placeholder text not being cutted out properly

Commits 2f91636, c8104d4

A very hacky way to force the input to breaks the text by doing ellipsis instead of directly cut it.

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4. Fix Chrome 17 About box having Chrome 21's size

Commit 045321b

This seems to be a missing change from the addition of Chrome 17 to Geckium

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Some fixes are probably needed, as I tested it using weird and painful methods.
I put them as a draft but despite the "No update" text fix that is solid, the others are... ehm... more tinkering that a proper fix?

[Kiki79250CoC]

Verifications needed to check fusionability of this artisanal-tested ("compiled" by hand with Notepad++) PR.

(Oui. I'm a compiler. A human-architecture-based compiler.)

[angelbruni]

I will check this tomorrow, thanks :O

[Kiki79250CoC]

Yeah I see, my choice was about the fact it must apply on the root of the CSS, so as it wasn't specific to any version, I though it was more appropriate to specify version as 0 to mean "not version-specific".

Nevertheless I changed that to chrome-1.

[angelbruni]

Thanks!