Make selection blue instead of orange

[paulrouget]

PR #10176 add a background color for selected text. It uses a builtin color until ::selection is supported. Orange makes sense for Linux. Let's make it blue for windows and mac. See #10231 (comment)

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This change is

[highfive]

Warning

• These commits modify layout code, but no tests are modified. Please consider adding a test!

[paulrouget]

(need to update the test)

[paulrouget]

So, native widget selection colors are:

• linux, ubuntu theme, white on orange (but really, it depends on the gtk theme, which is usually blue when it's not ubuntu)
• osx, black on light blue
• windows, white on dark blue

And for browserhtml, we need black on light blue.

Until we get some support for querying the OS widget, let's go for what makes sense for browserhtml.

[SimonSapin]

Until we get some support for querying the OS widget

Unless we have designers making sure everything works well in every possible configuration (which even Firefox apparently doesn’t), I’m strongly against querying the OS for colors. I use the "dark" variation of GNOME’s default theme (texts are white on dark grey backgrounds) but Firefox is utterly broken with that theme: many things end up with unreadable black text on dark background, and dark background buttons and input fields look very out of place in websites with otherwise light background.

The 15-years-old bug on this is https://bugzilla.mozilla.org/show_bug.cgi?id=70315 , still relevant with the recent switch to GTK 3.

To make Firefox usable I launch it with a script that sets an environment variable to select the light GTK theme.

[paulrouget]

Agreed.

[mbrubeck]

@bors-servo r+

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Reviewed 3 of 3 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from the review on Reviewable.io

[bors-servo]

📌 Commit 2bbf35f has been approved by mbrubeck

[pcwalton]

Maybe make this a pref? (I don't object to the change in this PR though.)

[bors-servo]

⌛ Testing commit 2bbf35f with merge cf4fa0a...

[bors-servo]

☀️ Test successful - android, arm32, gonk, linux-dev, linux-rel, mac-dev-unit, mac-rel-css, mac-rel-wpt, status-appveyor

[frewsxcv]

Do we have the ability to access https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSColor_Class/#//apple_ref/occ/clm/NSColor/selectedTextColor ?

[paulrouget]

Do we have the ability to access https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSColor_Class/#//apple_ref/occ/clm/NSColor/selectedTextColor ?

We could add that to glutin, or have any widget code that would give us these colors for the 3 platforms. We will have similar issues for buttons, checkboxes, text input (etc) shapes and colors.

I personally believe that content should not match the OS colors/shapes. Web developers fight against it all the time and browsers have inconsistent behaviors.

[frewsxcv]

Fair enough, thanks for the explanation