Presentation API: reject screen availability observing on Android low ram devices.

content/public/browser/presentation_screen_availability_listener.h

Index: content/public/browser/presentation_screen_availability_listener.h
diff --git a/content/public/browser/presentation_screen_availability_listener.h b/content/public/browser/presentation_screen_availability_listener.h
index 4580ddf0501d3ade4e6168bc18882b289749b0be..473981c2359bd9502b47eadc5992ca9a1eceecf0 100644
--- a/content/public/browser/presentation_screen_availability_listener.h
+++ b/content/public/browser/presentation_screen_availability_listener.h
@@ -26,6 +26,11 @@ class CONTENT_EXPORT PresentationScreenAvailabilityListener {
   // Called when screen availability for the associated Presentation URL has
   // changed to |available|.
   virtual void OnScreenAvailabilityChanged(bool available) = 0;
+
+  // Callend when screen availability monitoring is not supported by the
+  // by the implementation because of system limitations like running low on
+  // battery or having resource constraints.
+  virtual void OnScreenAvailabilityNotSupported() = 0;
 };
 
 }  // namespace content