[scheduler] Use Finch to control background throttling.

content/public/common/web_preferences.h

Index: content/public/common/web_preferences.h
diff --git a/content/public/common/web_preferences.h b/content/public/common/web_preferences.h
index 9759112e1eabdcdf6123500823acd08a50ec2d9b..9702484f6eb0da70a52d612e79362f5821da64ad 100644
--- a/content/public/common/web_preferences.h
+++ b/content/public/common/web_preferences.h
@@ -210,6 +210,14 @@ struct CONTENT_EXPORT WebPreferences {
   // Cues will not be placed in this margin area.
   float text_track_margin_percentage;
 
+  // Specifies aggressiveness of background tab throttling.
+  // expensive_background_throttling_cpu_budget is given in percentages,
+  // other values are in seconds.
+  float expensive_background_throttling_cpu_budget;
+  float expensive_background_throttling_initial_budget;
+  float expensive_background_throttling_max_budget;
+  float expensive_background_throttling_max_delay;
+
 #if defined(OS_ANDROID)
   bool text_autosizing_enabled;
   float font_scale_factor;