Removing getSystemPreferredDisplayMode and adding it as part of
DynamicDisplayInfo

Bug: 209598222
Test: atest CtsBootDisplayModeTestCases
Test: atest libcompositionengine_test
Change-Id: I1ce0a5a3916b14e25212dd1d2fc4f5e82674fcd1
diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index d2accaa..ad44b16 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -157,6 +157,9 @@
     // respectively if hardware composer doesn't return meaningful values.
     HdrCapabilities getHdrCapabilities() const;
 
+    // Returns the boot display mode preferred by the implementation.
+    ui::DisplayModeId getPreferredBootModeId() const;
+
     // Return true if intent is supported by the display.
     bool hasRenderIntent(ui::RenderIntent intent) const;