Editor display changes (#1036)

* Update style.less

The first change returns the background pattern as in the stable version.

The second change is to fix #downloadArea overlapping on the simulator. I don’t really understand why this bug is visible only in pxt-ev3. This bug is not detected in microbit, but the #downloadArea field is also larger than the height of #editortools itself. I compared the properties, but they seem to be all the same.

* revet-editortools-overflow-hidden

* Update style.less

Filling the background color is not required, because The #editortools parent element already has a background fill.

theme/style.less

@@ -115,14 +115,10 @@
     text-transform: lowercase;
 }
 
-#filelist {
+#simulator .editor-sidebar {
     background: @simulatorBackground data-uri("../docs/static/backgrounds/simulator.png") 0 0 repeat !important;
 }
 
-#downloadArea {
-    background: @legoGreyLight;
-}
-
 /* Editor download dialog */
 .ui.downloaddialog.modal>.content {
     padding: 1rem;