SF: Fix libcompositionengine_test Expectations around display IDs

https://googleplex-android-review.git.corp.google.com/c/platform/frameworks/native/+/31654940
seems to have introduced a regression in libcompositionengine_test
around CompositionEngineTest SetUp().

This CL fixes this issue.

Flag: EXEMPT bugfix
Bug: 403479642
Test: libcompositionengine_test
Change-Id: Ic8c05895f084faaffb2d228d2630ce995df572bd

Author: stagadish

services/surfaceflinger/CompositionEngine/tests/CompositionEngineTest.cpp

@@ -62,10 +62,15 @@ struct CompositionEngineTest : public testing::Test {
     void SetUp() override {
         EXPECT_CALL(*mOutput1, getDisplayId)
                 .WillRepeatedly(Return(std::make_optional<DisplayId>(kDisplayId1)));
+        EXPECT_CALL(*mOutput1, getDisplayIdVariant).WillRepeatedly(Return(kDisplayId1));
+
         EXPECT_CALL(*mOutput2, getDisplayId)
                 .WillRepeatedly(Return(std::make_optional<DisplayId>(kDisplayId2)));
+        EXPECT_CALL(*mOutput2, getDisplayIdVariant).WillRepeatedly(Return(kDisplayId2));
+
         EXPECT_CALL(*mOutput3, getDisplayId)
                 .WillRepeatedly(Return(std::make_optional<DisplayId>(kDisplayId3)));
+        EXPECT_CALL(*mOutput3, getDisplayIdVariant).WillRepeatedly(Return(kDisplayId3));
 
         // Most tests will depend on the outputs being enabled.
         for (auto& state : mOutputStates) {