Enable Dark theme

TODO:
- fix the app freeze when user changes the app theme.

Riot/ViewController/RoomFilesSearchViewController.m

@@ -72,6 +72,23 @@
 - (void)userInterfaceThemeDidChange
 {
     self.defaultBarTintColor = kRiotSecondaryBgColor;
+    self.barTitleColor = kRiotPrimaryTextColor;
+    
+    // Check the table view style to select its bg color.
+    self.searchTableView.backgroundColor = ((self.searchTableView.style == UITableViewStylePlain) ? kRiotPrimaryBgColor : kRiotSecondaryBgColor);
+    self.view.backgroundColor = self.searchTableView.backgroundColor;
+    
+    self.noResultsLabel.textColor = kRiotPrimaryBgColor;
+    
+    if (self.searchTableView.dataSource)
+    {
+        [self.searchTableView reloadData];
+    }
+}
+
+- (UIStatusBarStyle)preferredStatusBarStyle
+{
+    return kRiotDesignStatusBarStyle;
 }
 
 - (void)destroy
@@ -130,6 +147,29 @@
 
 #pragma mark - Override UITableView delegate
 
+- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath;
+{
+    cell.backgroundColor = kRiotPrimaryBgColor;
+    
+    // Update the selected background view
+    if (kRiotSelectedBgColor)
+    {
+        cell.selectedBackgroundView = [[UIView alloc] init];
+        cell.selectedBackgroundView.backgroundColor = kRiotSelectedBgColor;
+    }
+    else
+    {
+        if (tableView.style == UITableViewStylePlain)
+        {
+            cell.selectedBackgroundView = nil;
+        }
+        else
+        {
+            cell.selectedBackgroundView.backgroundColor = nil;
+        }
+    }
+}
+
 - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
 {
     // Data in the cells are actually Vector RoomBubbleCellData