Update chooser row view when mouse click down and move over rows

chrome/browser/ui/cocoa/website_settings/chooser_bubble_ui_cocoa.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/website_settings/chooser_bubble_ui_cocoa.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 195 matching lines @@
 
 - (void)updateTableView {
   [chooserContentView_ updateTableView];
 }
 
 - (void)tableViewSelectionDidChange:(NSNotification*)aNotification {
   [chooserContentView_ updateContentRowColor];
   [connectButton_ setEnabled:[tableView_ numberOfSelectedRows] > 0];
 }
 
+// Selection changes (while the mouse button is still down).
+- (void)tableViewSelectionIsChanging:(NSNotification*)aNotification {
+  [chooserContentView_ updateContentRowColor];
+  [connectButton_ setEnabled:[tableView_ numberOfSelectedRows] > 0];
+}
+
 - (void)updateAnchorPosition {
   [self setParentWindow:[self getExpectedParentWindow]];
   [self setAnchorPoint:[self getExpectedAnchorPoint]];
 }
 
 - (NSPoint)getExpectedAnchorPoint {
   NSPoint anchor;
   if ([self hasLocationBar]) {
     LocationBarViewMac* locationBar =
         [[[self getExpectedParentWindow] windowController] locationBarBridge];
@@ skipping 90 matching lines @@
 }
 
 void ChooserBubbleUiCocoa::UpdateAnchorPosition() {
   if (chooser_bubble_ui_controller_)
     [chooser_bubble_ui_controller_ updateAnchorPosition];
 }
 
 void ChooserBubbleUiCocoa::OnBubbleClosing() {
   chooser_bubble_ui_controller_ = nil;
 }