src/: Update the remaining include paths of string_split.h to its new location.

cc/heads_up_display_layer_impl.cc

 // Copyright 2012 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 "cc/heads_up_display_layer_impl.h"
 
-#include "base/string_split.h"
 #include "base/stringprintf.h"
+#include "base/strings/string_split.h"
 #include "cc/debug_colors.h"
 #include "cc/debug_rect_history.h"
 #include "cc/frame_rate_counter.h"
 #include "cc/layer_tree_impl.h"
 #include "cc/memory_history.h"
 #include "cc/paint_time_counter.h"
 #include "cc/quad_sink.h"
 #include "cc/renderer.h"
 #include "cc/texture_draw_quad.h"
 #include "cc/tile_manager.h"
@@ skipping 507 matching lines @@
 
     canvas->restore();
 }
 
 const char* HeadsUpDisplayLayerImpl::layerTypeAsString() const
 {
     return "HeadsUpDisplayLayer";
 }
 
 }  // namespace cc