SF: Decouple EventThread from DisplayDevice

EventThread uses DisplayDevice::DisplayType constants, which will be
removed in a follow-up CL. This CL replaces them with local constants as
a stopgap until stable display IDs are propagated through the SF/WM
interface.

Bug: 74619554
Test: libsurfaceflinger_unittest
Change-Id: I68be363dc58c5e3aa17d05fba156d520a01fa775
diff --git a/services/surfaceflinger/tests/unittests/DisplayTransactionTest.cpp b/services/surfaceflinger/tests/unittests/DisplayTransactionTest.cpp
index 7928cba..8d18d76 100644
--- a/services/surfaceflinger/tests/unittests/DisplayTransactionTest.cpp
+++ b/services/surfaceflinger/tests/unittests/DisplayTransactionTest.cpp
@@ -1165,13 +1165,23 @@
     Case::PerFrameMetadataSupport::setupComposerCallExpectations(this);
 
     EXPECT_CALL(*mSurfaceInterceptor, saveDisplayCreation(_)).Times(1);
-    EXPECT_CALL(*mEventThread, onHotplugReceived(Case::Display::TYPE, true)).Times(1);
+    EXPECT_CALL(*mEventThread,
+                onHotplugReceived(Case::Display::TYPE == DisplayDevice::DISPLAY_PRIMARY
+                                          ? EventThread::DisplayType::Primary
+                                          : EventThread::DisplayType::External,
+                                  true))
+            .Times(1);
 }
 
 template <typename Case>
 void HandleTransactionLockedTest::setupCommonCallExpectationsForDisconnectProcessing() {
     EXPECT_CALL(*mSurfaceInterceptor, saveDisplayDeletion(_)).Times(1);
-    EXPECT_CALL(*mEventThread, onHotplugReceived(Case::Display::TYPE, false)).Times(1);
+    EXPECT_CALL(*mEventThread,
+                onHotplugReceived(Case::Display::TYPE == DisplayDevice::DISPLAY_PRIMARY
+                                          ? EventThread::DisplayType::Primary
+                                          : EventThread::DisplayType::External,
+                                  false))
+            .Times(1);
 }
 
 template <typename Case>