fix #316571 updated close icon file reference for MIDI import panel

[jeetee]

Opted for the toolbar- version over the dialog- version due to better matching size with the arrows

Resolves: https://musescore.org/en/node/316571

got overlooked in #7072

• I signed CLA
• I made sure the code in the PR follows the coding rules
• I made sure the code compiles on my machine
• I made sure there are no unnecessary changes in the code
• I made sure the title of the PR reflects the core meaning of the issue you are solving
• I made sure the commit message(s) contain a description and answer the question "Why do those changes fix that particular issue?" or "Why are those changes really necessary as improvements?"
• I made sure the commit message title starts with "fix #424242:" if there is a related issue
• [N/A] I created the test (mtest, vtest, script test) to verify the changes I made

[cbjeukendrup]

But where is toolbar-close.png? It doesn't seem to exist, and in the artifact the icon doesn't show up for me. I think it would be the best to take :/data/icons/window-close.svg.

Futhermore, in mscore/importmidi_ui/importmidi_panel.cpp you need two add these lines:

+      _ui->toolButtonHideMidiPanel->setIcon(*icons[int(Icons::close_ICON)]);
+      _ui->pushButtonUp->setIcon(*icons[int(Icons::arrowUp_ICON)]);
       _ui->pushButtonDown->setIcon(*icons[int(Icons::arrowDown_ICON)]);

And in mscore/data/icons/window-close.svg:

- <svg id="Layer_1" data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 48 48">
+ <svg fill="#3B3F45" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 48 48">

This is needed to get it to work correctly with dark mode. However, switching between light and dark mode won't work, like in very many places in the program. That would be quite complicated to solve, I think.

[cbjeukendrup]

(And yes, it's true that you need to hard-code the color into the svg, so that it is replaced in MIconEnginePrivate::loadDataForModeAndState.)

(I'm looking forward to MuseScore4's icons system, which is a lot less complicated...)

[jeetee]

@cbjeukendrup will PR a better suited fix.