Fix#4539. Conditional Formatting was recently added to Html Writer. It works fine when not using inline Css. However, when using inline Css, the code inadvertently added 2 different `style` attributes (one for the unconditional style and one for the conditional style) to the same cell. This is not valid html, and results in losing the conditional styling. This PR combines the two `style` attributes into one, which will now come after the `class`, `colspan`, and `rowspan` attributes.
Aside from the new tests, this PR changes an unusually large number of existing tests. While this might normally be considered a red flag, it is not a problem here. All of the changes involve merely changing the order of attributes within html tags; none of them affect how the generated html would appear in a browser.
Fix#3557. Borders around merged cells are not handled correctly for Mpdf. Although a perfectly acceptable workaround is suggested in the issue, it would be better if things just worked without the workaround. Html and Dompdf work with the existing code. As it turns out, Tcpdf does not work, but for a different reason than Mpdf.
Mpdf was not working because Mpdf does not honor the `!important` attribute in Css. We can get it working almost perfectly by suppressing `border*:none`; the exception is fairly Byzantine, and I'll be glad to discuss the matter should anyone report a problem with it. At any rate, it's not working now in the exception case, so we won't be any worse off.
Tcpdf was not working because the merging of attributes happened only when `useInlineCss` was not being used, but Tcpdf does use it. Merging of border attributes is now added for useInlineCss.
oleibman