Experiment with more aggressive MSE GC on memory pressure

content/browser/renderer_host/render_view_host_impl.cc

Index: content/browser/renderer_host/render_view_host_impl.cc
diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 0ada79de92bedcf2d7917b2db4b4956a502eaa33..28414c4406d7793c444839ec6a65eca4f17fdd78 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -550,6 +550,13 @@ WebPreferences RenderViewHostImpl::ComputeWebkitPrefs() {
               "max_keyframe_distance_ms",
               base::TimeDelta::FromSeconds(10).InMilliseconds()));
 
+  // TODO(servolk, asvitkine): Query the value directly when it is available in
+  // the renderer process. See https://crbug.com/681160.
+  prefs.enable_instant_source_buffer_gc =
+      variations::GetVariationParamByFeatureAsBool(
+          media::kMemoryPressureBasedSourceBufferGC,
+          "enable_instant_source_buffer_gc", false);
+
   std::map<std::string, std::string> expensive_background_throttling_prefs;
   variations::GetVariationParamsByFeature(
       features::kExpensiveBackgroundTimerThrottling,