Suppress all hidden abstract methods in constructable classes.

Having a hidden abstract method for a class that can be extended
means that public implementors cannot implement these hidden methods
posing a risk that custom implementations will not have required
abstract methods resulting in an exception.

Bug: 151134792
Test: make update-api
Change-Id: I758d12465fabc671be19bedeeceb16885de23c87
Exempt-From-Owner-Approval: large scale suppression of existing issues,
    no-op in terms of behavior

core/java/android/inputmethodservice/AbstractInputMethodService.java

@@ -202,6 +202,7 @@ public abstract class AbstractInputMethodService extends Service
      * @param args The arguments passed to the dump method.
      * @hide
      */
+    @SuppressWarnings("HiddenAbstractMethod")
     abstract void dumpProtoInternal(FileDescriptor fd, String[] args);
 
     /**