Update from https://crrev.com/304121

cc/trees/layer_tree_settings.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_settings.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 
 namespace cc {
 
 LayerTreeSettings::LayerTreeSettings()
     : impl_side_painting(false),
       allow_antialiasing(true),
       force_antialiasing(false),
+      force_blending_with_shaders(false),
       throttle_frame_production(true),
       single_thread_proxy_scheduler(true),
-      begin_frame_scheduling_enabled(false),
+      use_external_begin_frame_source(false),
+      forward_begin_frames_to_children(false),
       main_frame_before_activation_enabled(false),
       using_synchronous_renderer_compositor(false),
       disable_hi_res_timer_tasks_on_battery(false),
       report_overscroll_only_for_scrollable_axes(false),
       per_tile_painting_enabled(false),
       partial_swap_enabled(false),
       accelerated_animation_enabled(true),
       can_use_lcd_text(true),
       use_distance_field_text(false),
       should_clear_root_render_pass(true),
       gpu_rasterization_enabled(false),
       gpu_rasterization_forced(false),
       create_low_res_tiling(false),
       scrollbar_animator(NoAnimator),
       scrollbar_fade_delay_ms(0),
       scrollbar_fade_resize_delay_ms(0),
       scrollbar_fade_duration_ms(0),
       solid_color_scrollbar_color(SK_ColorWHITE),
       calculate_top_controls_position(false),
       timeout_and_draw_when_animation_checkerboards(true),
       maximum_number_of_failed_draws_before_draw_is_forced_(3),
       layer_transforms_should_scale_layer_contents(false),
       minimum_contents_scale(0.0625f),
       low_res_contents_scale_factor(0.25f),
       top_controls_height(0.f),
       top_controls_show_threshold(0.5f),
       top_controls_hide_threshold(0.5f),
       refresh_rate(60.0),
+      background_animation_rate(1.0),
       max_partial_texture_updates(std::numeric_limits<size_t>::max()),
       default_tile_size(gfx::Size(256, 256)),
       max_untiled_layer_size(gfx::Size(512, 512)),
       default_tile_grid_size(gfx::Size(256, 256)),
       minimum_occlusion_tracking_size(gfx::Size(160, 160)),
       use_pinch_zoom_scrollbars(false),
       use_pinch_virtual_viewport(false),
       // At 256x256 tiles, 128 tiles cover an area of 2048x4096 pixels.
       max_tiles_for_interest_area(128),
       skewport_target_time_multiplier(1.0f),
       skewport_extrapolation_limit_in_content_pixels(2000),
       max_unused_resource_memory_percentage(100),
       max_memory_for_prepaint_percentage(100),
       highp_threshold_min(0),
       strict_layer_property_change_checking(false),
       use_one_copy(false),
       use_zero_copy(false),
       ignore_root_layer_flings(false),
       use_rgba_4444_textures(false),
       texture_id_allocation_chunk_size(64),
       scheduled_raster_task_limit(32),
       use_occlusion_for_tile_prioritization(false),
       record_full_layer(false) {
 }
 
 LayerTreeSettings::~LayerTreeSettings() {}
 
 }  // namespace cc