Update setHdrConversionStrategy to return the preferredHdrOutput type

Bug: 268336382
Test: atest VtsHalGraphicsComposer3_TargetTest
Change-Id: I6ac912ac8a0329f4ea32acad657e44b473660c42
diff --git a/graphics/composer/aidl/vts/VtsComposerClient.h b/graphics/composer/aidl/vts/VtsComposerClient.h
index aee46d2..81a62b3 100644
--- a/graphics/composer/aidl/vts/VtsComposerClient.h
+++ b/graphics/composer/aidl/vts/VtsComposerClient.h
@@ -166,7 +166,8 @@
     std::pair<ScopedAStatus, std::vector<common::HdrConversionCapability>>
     getHdrConversionCapabilities();
 
-    ScopedAStatus setHdrConversionStrategy(const common::HdrConversionStrategy& conversionStrategy);
+    std::pair<ScopedAStatus, common::Hdr> setHdrConversionStrategy(
+            const common::HdrConversionStrategy& conversionStrategy);
 
     std::pair<ScopedAStatus, common::Transform> getDisplayPhysicalOrientation(int64_t display);