Add flag for HDR screenshots

Bug: 329470026
Flag: com.android.graphics.surfaceflinger.flags.true_hdr_screenshots
Test: builds
Change-Id: I13650b4433ab062b7f5f67005c0948b417c1f269
diff --git a/services/surfaceflinger/common/FlagManager.cpp b/services/surfaceflinger/common/FlagManager.cpp
index 07c720f..8ec908f 100644
--- a/services/surfaceflinger/common/FlagManager.cpp
+++ b/services/surfaceflinger/common/FlagManager.cpp
@@ -155,6 +155,7 @@
     DUMP_READ_ONLY_FLAG(force_compile_graphite_renderengine);
     DUMP_READ_ONLY_FLAG(single_hop_screenshot);
     DUMP_READ_ONLY_FLAG(trace_frame_rate_override);
+    DUMP_READ_ONLY_FLAG(true_hdr_screenshots);
 
 #undef DUMP_READ_ONLY_FLAG
 #undef DUMP_SERVER_FLAG
@@ -259,6 +260,7 @@
 FLAG_MANAGER_READ_ONLY_FLAG(flush_buffer_slots_to_uncache, "");
 FLAG_MANAGER_READ_ONLY_FLAG(force_compile_graphite_renderengine, "");
 FLAG_MANAGER_READ_ONLY_FLAG(single_hop_screenshot, "");
+FLAG_MANAGER_READ_ONLY_FLAG(true_hdr_screenshots, "debug.sf.true_hdr_screenshots");
 
 /// Trunk stable server flags ///
 FLAG_MANAGER_SERVER_FLAG(refresh_rate_overlay_on_external_display, "")