don't crash apps that depend on missing Gservices provider

This allows apps that have minor dependency on GSF/GmsCore (EuiccSupportPixel, Google Camera etc)
to work without having any of GSF, GmsCore, Play Store installed.

Gservices provider is currently hosted by GSF, soon to be hosted by GmsCore.

core/java/android/content/ContentResolver.java

@@ -2755,6 +2755,11 @@ public final void registerContentObserver(Uri uri, boolean notifyForDescendents,
                     observer.getContentObserver(), userHandle, mTargetSdkVersion);
         } catch (RemoteException e) {
             throw e.rethrowFromSystemServer();
+        } catch (SecurityException se) {
+            if ("com.google.android.gsf.gservices".equals(uri.getAuthority())) {
+                return;
+            }
+            throw se;
         }
     }