Don't paint the throbber animation while dragging.

chrome/browser/gtk/tabs/tab_strip_gtk.cc

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/gtk/tabs/tab_strip_gtk.h"
 
 #include <algorithm>
 
 #include "app/gtk_dnd_util.h"
 #include "app/gfx/canvas_paint.h"
@@ skipping 1768 matching lines @@
   if (gdk_region_empty(event->region))
     return TRUE;
 
   // If we're only repainting favicons, optimize the paint path and only draw
   // the favicons.
   GdkRectangle* rects;
   gint num_rects;
   gdk_region_get_rectangles(event->region, &rects, &num_rects);
   qsort(rects, num_rects, sizeof(GdkRectangle), CompareGdkRectangles);
   std::vector<int> tabs_to_repaint;
-  if (tabstrip->CanPaintOnlyFavIcons(rects, num_rects, &tabs_to_repaint)) {
+  if (!tabstrip->IsDragSessionActive() &&
+      tabstrip->CanPaintOnlyFavIcons(rects, num_rects, &tabs_to_repaint)) {
     tabstrip->PaintOnlyFavIcons(event, tabs_to_repaint);
     g_free(rects);
     return TRUE;
   }
   g_free(rects);
 
   // TODO(jhawkins): Ideally we'd like to only draw what's needed in the damage
   // rect, but the tab widgets overlap each other, and painting on one widget
   // will cause an expose-event to be sent to the widgets underneath.  The
   // underlying widget does not need to be redrawn as we control the order of
@@ skipping 211 matching lines @@
 
   // Let the middle mouse button initiate clicks as well.
   gtk_util::SetButtonTriggersNavigation(button->widget());
   g_signal_connect(G_OBJECT(button->widget()), "clicked",
                    G_CALLBACK(OnNewTabClicked), this);
   GTK_WIDGET_UNSET_FLAGS(button->widget(), GTK_CAN_FOCUS);
   gtk_fixed_put(GTK_FIXED(tabstrip_.get()), button->widget(), 0, 0);
 
   return button;
 }