Revert "Mark @FlaggedApi flags as exported"

Revert submission 30583310-fix-non-exported-flags

Reason for revert: Likely culprit for b/381233132  - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Reverted changes: /q/submissionid:30583310-fix-non-exported-flags

Change-Id: I93795666bc97502649041a9f0052ec95d6295258

Author: Chaitanya Cheemala (xWF)

services/surfaceflinger/surfaceflinger_flags_new.aconfig

@@ -31,7 +31,6 @@ flag {
   description: "New SDK Surface#setFrameRate API and Surface.FrameRateParams for Android 16"
   bug: "356987016"
   is_fixed_read_only: true
-  is_exported: true
 } # arr_setframerate_api
 
 flag {
@@ -40,7 +39,6 @@ flag {
   description: "New SDK SurfaceControl.Transaction#setFrameRate API for Android 16"
   bug: "356987016"
   is_fixed_read_only: true
-  is_exported: true
 } # arr_surfacecontrol_setframerate_api
 
 flag {