MDL-42392 Blocks: Do not hide blocks if JS is disabled

With JS disabled, it is not possible to change the block visibility
user preference and therefore not possible to show content which was
hidden.

Since the block hiding functionality is a nicety, and we have no controls
to show and hide the blocks when JS is disabled, we should instead show the
block content regardless of the user preference.

theme/afterburner/style/afterburner_blocks.css

@@ -16,7 +16,7 @@ Block
 .block .content {
     padding:10px;
 }
-.block.hidden .content {
+.jsenabled .block.hidden .content {
     display: none;
 }
 .block .content .userpicture {

theme/base/style/blocks.css

@@ -8,7 +8,7 @@
 .block .header .commands .icon img {width:12px;height:12px;}
 .block .header .commands img.actionmenu {width:auto;}
 .block .content {padding:4px;}
-.block.hidden .content {display: none;}
+.jsenabled .block.hidden .content {display: none;}
 .block .content .userpicture {width:16px;height:16px;margin-right:6px;}
 .block .content .list li.listentry {clear:both;}
 .block .content .list .c0 {display:inline;}

theme/bootstrapbase/less/moodle/blocks.less

@@ -46,7 +46,7 @@
     margin: 5px 0;
 }
 
-.block.hidden .content {
+.jsenabled .block.hidden .content {
     display: none;
 }