Mac: Fix throbber not spinning after dragging tabs.

We want the throbber to spin when it's attached to a window, and that window is
not miniaturized.
We were calling -updateAnimation: from -viewWillMoveToWindow where [self window]
is still the old window. We want to update the animation based on the new
window, so the fix is to call it from -viewDidMoveToWindow.

BUG=361969

Review URL: https://codereview.chromium.org/235583002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263363 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/cocoa/sprite_view.mm

@@ -54,7 +54,9 @@ - (void)viewWillMoveToWindow:(NSWindow*)newWindow {
                name:NSWindowDidDeminiaturizeNotification
              object:newWindow];
   }
+}
 
+- (void)viewDidMoveToWindow {
   [self updateAnimation:nil];
 }