[Material][Mac] Fix the indicator and close button in a dragged tab

chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm

Index: chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm b/chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm
index 8db7968b427057de5b6881c7316ddb10a8bbdbc7..a73c86473a44fe9ceebf5455016e3a46f85ffc5e 100644
--- a/chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm
+++ b/chrome/browser/ui/cocoa/tabs/alert_indicator_button_cocoa.mm
@@ -73,6 +73,12 @@ class FadeAnimationDelegate : public gfx::AnimationDelegate {
   [super removeFromSuperview];
 }
 
+- (void)viewDidMoveToWindow {
+  // In Material Design, the icon color depends on the theme. When the tab
+  // is moved into another window, make sure that it updates the theme.
+  [self updateIconForState:showingAlertState_];
+}
+
 - (void)updateIconForState:(TabAlertState)aState {
   if (aState != TabAlertState::NONE) {
     TabView* const tabView = base::mac::ObjCCast<TabView>([self superview]);