content: Global times in a link span should be link-colored, but aren't

[chrisbobbe]

Web:

Mobile:

We even have a test that the clock icon and the date-time text are the same color as each other:

• when the global time appears in a link span, and
• when it doesn't

    void testIconAndTextSameColor(String description, String html) {
      testWidgets('clock icon and text are the same color: $description', (tester) async {
        await prepareContent(tester,
          // We use the self-account's time-format setting.
          wrapWithPerAccountStoreWidget: true,
          plainContent(html));

        final icon = tester.widget<Icon>(
          find.descendant(of: find.byType(GlobalTime),
            matching: find.byIcon(ZulipIcons.clock)));

        final textColor = mergedStyleOf(tester,
          findAncestor: find.byType(GlobalTime), renderedTextRegexp)!.color;
        check(textColor).isNotNull();

        check(icon).color.isNotNull().isSameColorAs(textColor!);
      });
    }

    testIconAndTextSameColor('common case', '<p>$timeSpanHtml</p>');
    testIconAndTextSameColor('inside link', '<p><a href="https://example/">$timeSpanHtml</a></p>');

But the in-link-span test doesn't do the further check that that color is blue, which allowed this bug to slip through. 🫠

[chrisbobbe]

Actually it's not just link coloring; see other span types:

Web:

Mobile:

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I notice that web doesn't apply the strikethrough, but probably should, for a use case like striking out proposed meeting times.