Media: Ensure variables in the attachment details template have defined defaults.

* Adds styling to the upload progress bar in the attachment details template.
* Defines the `filename` attribute when Plupload creates the client-side `Attachment` model.

fixes #22410, see #21390.


git-svn-id: https://develop.svn.wordpress.org/trunk@22543 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/media.php

@@ -1454,7 +1454,7 @@ function wp_print_media_templates( $attachment ) {
 			<div class="details">
 				<div class="filename">{{ filename }}</div>
 				<div class="uploaded">{{ dateFormatted }}</div>
-				<# if ( 'image' === type ) { #>
+				<# if ( 'image' === type && ! uploading ) { #>
 					<div class="dimensions">{{ width }} &times; {{ height }}</div>
 				<# } #>
 			</div>