Remove deprecated GNSS APIs + add nullability

Cleans up location APIs by removing old deprecated APIs (deprecated
since API 24) and adding nullability annotations everywhere.

Bug:126698813,126701422,126702274
Test: built
Change-Id: I6caf7f9778100bb3eee53178c25ce1694fb2d395
diff --git a/api/system-removed.txt b/api/system-removed.txt
index 22a3fb3..7e04469 100644
--- a/api/system-removed.txt
+++ b/api/system-removed.txt
@@ -60,6 +60,17 @@
 
 }
 
+package android.location {
+
+  public class LocationManager {
+    method @Deprecated public boolean addGpsMeasurementListener(android.location.GpsMeasurementsEvent.Listener);
+    method @Deprecated public boolean addGpsNavigationMessageListener(android.location.GpsNavigationMessageEvent.Listener);
+    method @Deprecated public void removeGpsMeasurementListener(android.location.GpsMeasurementsEvent.Listener);
+    method @Deprecated public void removeGpsNavigationMessageListener(android.location.GpsNavigationMessageEvent.Listener);
+  }
+
+}
+
 package android.media.tv {
 
   public final class TvInputManager {