Add FILEINFO_MIME_TYPE support (fix incorrect bugfix)

[maeln0r]

In src/PhpImap/IncomingMailAttachment.php

if ((FILEINFO_MIME == $fileinfo_const) && (false != $this->mimeType)) {
            return $this->mimeType;
}

$this->mimeType - currently never set, condition always false. Deleted as unnecessary.

Added default field definition in src/PhpImap/Mailbox.php

$attachment->mimeType = $attachment->getFileInfo(FILEINFO_MIME_TYPE);

Also i found incorrect use of mime type in src/PhpImap/IncomingMail.php -> embedImageAttachments()

$contentType = (string) $attachment->getFileInfo(FILEINFO_MIME);
$base64encoded = \base64_encode($contents);
$replacement = 'data:'.$contentType.';base64, '.$base64encoded;

For example for jpeg image FILEINFO_MIME is image/jpeg; charset=binary, and for correct base64 need only mime type (without encoding) FILEINFO_MIME_TYPE -> image/jpeg

[Sebbo94BY]

Can you please update your description of this pull request with a english text?

Some before and after examples would be also good.

[Sebbo94BY]

Thanks for the update.

If the MIM type usage in embedImageAttachments() is also incorrect implemented, wouldn't it make sense to update it with this merge request as well? Or do you think, this will break something?

[maeln0r]

Thanks for the update.

If the MIM type usage in embedImageAttachments() is also incorrect implemented, wouldn't it make sense to update it with this merge request as well? Or do you think, this will break something?

That's right, I fixed it here: c181db6