cc: Change preraster/predecode split to be half of max skewport extent.

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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/trees/layer_tree_host_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 205 matching lines @@
       cached_managed_memory_policy_(settings.memory_policy_),
       is_synchronous_single_threaded_(!task_runner_provider->HasImplThread() &&
                                       !settings.single_thread_proxy_scheduler),
       // Must be initialized after is_synchronous_single_threaded_ and
       // task_runner_provider_.
       tile_manager_(this,
                     GetTaskRunner(),
                     is_synchronous_single_threaded_
                         ? std::numeric_limits<size_t>::max()
                         : settings.scheduled_raster_task_limit,
-                    settings.use_partial_raster,
-                    settings.max_preraster_distance_in_screen_pixels),
+                    settings.use_partial_raster),
       pinch_gesture_active_(false),
       pinch_gesture_end_should_clear_scrolling_layer_(false),
       fps_counter_(
           FrameRateCounter::Create(task_runner_provider_->HasImplThread())),
       memory_history_(MemoryHistory::Create()),
       debug_rect_history_(DebugRectHistory::Create()),
       texture_mailbox_deleter_(new TextureMailboxDeleter(GetTaskRunner())),
       max_memory_needed_bytes_(0),
       resourceless_software_draw_(false),
       animation_host_(std::move(animation_host)),
@@ skipping 3958 matching lines @@
   if (is_visible) {
     worker_context_visibility_ =
         worker_context->CacheController()->ClientBecameVisible();
   } else {
     worker_context->CacheController()->ClientBecameNotVisible(
         std::move(worker_context_visibility_));
   }
 }
 
 }  // namespace cc