SF: Clean up FakeDisplayDeviceInjector TODO

Split the double-duty setDisplayModes API.

Bug: 241285876
Test: libsurfaceflinger_unittest
Change-Id: Id52a824d22c9a89b650a9c50d0093b95ecfd9123
Merged-In: Id52a824d22c9a89b650a9c50d0093b95ecfd9123
(cherry picked from commit aa73cf5ade78f45dac0ba6feb03f0501b7b80ead)
diff --git a/services/surfaceflinger/Scheduler/RefreshRateSelector.h b/services/surfaceflinger/Scheduler/RefreshRateSelector.h
index 4f5842a..5052e6e 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateSelector.h
+++ b/services/surfaceflinger/Scheduler/RefreshRateSelector.h
@@ -32,7 +32,6 @@
 #include <scheduler/Seamlessness.h>
 
 #include "DisplayHardware/DisplayMode.h"
-#include "DisplayHardware/HWComposer.h"
 #include "Scheduler/OneShotTimer.h"
 #include "Scheduler/StrongTyping.h"
 #include "ThreadContext.h"
@@ -297,6 +296,8 @@
     RefreshRateSelector(const RefreshRateSelector&) = delete;
     RefreshRateSelector& operator=(const RefreshRateSelector&) = delete;
 
+    const DisplayModes& displayModes() const { return mDisplayModes; }
+
     // Returns whether switching modes (refresh rate or resolution) is possible.
     // TODO(b/158780872): Consider HAL support, and skip frame rate detection if the modes only
     //  differ in resolution. Once Config::FrameRateOverride::Enabled becomes the default,