Fix: text color of the last event description was incorrect.

[nimau]

This PR fixes a problem where the font color of lastEventDescription is not updated when the theme changes.

In the RecentTableViewCell, the lastEventDescription label has a foreground color but most of the time it displays the roomCellData.lastEventAttributedTextMessage which is an attributed string containing its own set of text color attributes.

By default, this attributed string uses only the secondaryTextColor, but in some scenarios (such as a live broadcast), the text may have a different color.

This attributed string is calculated by the EventFormatter when updating the room summary. The solution chosen for this PR was add two custom attributes for this attributed string:

• themeIdentifierAttributeName: to store which theme was active when the attributed string was created
• themeColorNameAttributeName: to store the name for the color

Before rendering the attributed string, if it contains the themeIdentifierAttributeName attribute and the active theme doesn't match, then the colors for the string will be updated to the current theme using the themeColorNameAttributeName attribute.

[codecov]

Codecov Report

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Patch coverage: 0.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             develop    #7545   +/-   ##
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  Coverage           ?   12.36%           
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  Files              ?     1648           
  Lines              ?   163576           
  Branches           ?    67167           
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  Hits               ?    20231           
  Misses             ?   142680           
  Partials           ?      665           

Flag	Coverage Δ
uitests	55.06% <0.00%> (?)
unittests	6.21% <0.00%> (?)

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Impacted Files	Coverage Δ
Riot/Categories/NSAttributedString+Theme.swift	0.00% <0.00%> (ø)
Riot/Managers/Theme/ThemeService.swift	0.00% <0.00%> (ø)
...Modules/Common/Recents/Views/RecentTableViewCell.m	0.00% <0.00%> (ø)
Riot/Utils/EventFormatter.m	7.46% <0.00%> (ø)
Riot/Utils/ThemeColorResolver.swift	0.00% <0.00%> (ø)

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[sonarcloud]

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[pixlwave]

Nice, looks sane to me. Maybe now that there's a colour name it could use theme.performSelector(name) instead of a Mirror and reflection, but off the top of my head I'm not sure if Theme is coming directly from objc to allow that.

[nimau]

Nice, looks sane to me. Maybe now that there's a colour name it could use theme.performSelector(name) instead of a Mirror and reflection, but off the top of my head I'm not sure if Theme is coming directly from objc to allow that.

Hi @pixlwave, I tried but it doesn't seem possible on theme