Apply dark theme changes to media downloads.

Signal/src/ViewControllers/ConversationView/Cells/ConversationMediaView.swift

@@ -102,7 +102,7 @@ public class ConversationMediaView: UIView {
             return
         }
 
-        backgroundColor = UIColor.ows_gray05
+        backgroundColor = (Theme.isDarkThemeEnabled ? .ows_gray90 : .ows_gray05)
         let progressView = MediaDownloadView(attachmentId: attachmentId, radius: maxMessageWidth * 0.1)
         self.addSubview(progressView)
         progressView.autoPinEdgesToSuperviewEdges()
@@ -288,7 +288,7 @@ public class ConversationMediaView: UIView {
     }
 
     private func configure(forError error: MediaError) {
-        backgroundColor = UIColor.ows_gray05
+        backgroundColor = (Theme.isDarkThemeEnabled ? .ows_gray90 : .ows_gray05)
         let icon: UIImage
         switch (error) {
         case .failed:

Signal/src/ViewControllers/ConversationView/Cells/MediaDownloadView.swift

@@ -92,7 +92,8 @@ public class MediaDownloadView: UIView {
         bezierPath.addArc(withCenter: center, radius: innerRadius, startAngle: endAngle, endAngle: startAngle, clockwise: false)
 
         shapeLayer.path = bezierPath.cgPath
-        shapeLayer.fillColor = UIColor.ows_gray60.cgColor
+        let fillColor: UIColor = (Theme.isDarkThemeEnabled ? .ows_gray45 : .ows_gray60)
+        shapeLayer.fillColor = fillColor.cgColor
 
         CATransaction.commit()
     }