Replace DX DexMerger with D8 in platform

BUG: 73981693
Test: art/test.py --verbose -j200 --host -b
Change-Id: Idf7b71807019aca91094f69dba8c6b62e1a6bf16
diff --git a/test/run-test b/test/run-test
index 260a65a..5b43b52 100755
--- a/test/run-test
+++ b/test/run-test
@@ -50,11 +50,18 @@
 export USE_DESUGAR="true"
 export SMALI_ARGS=""
 
+# If d8 was not set by the environment variable, assume it is in the path.
+if [ -z "$D8" ]; then
+  export D8="d8"
+fi
+
 # If dx was not set by the environment variable, assume it is in the path.
 if [ -z "$DX" ]; then
   export DX="dx"
 fi
 
+export DXMERGER="$D8"
+
 # If jasmin was not set by the environment variable, assume it is in the path.
 if [ -z "$JASMIN" ]; then
   export JASMIN="jasmin"
@@ -65,11 +72,6 @@
   export SMALI="smali"
 fi
 
-# If dexmerger was not set by the environment variable, assume it is in the path.
-if [ -z "$DXMERGER" ]; then
-  export DXMERGER="dexmerger"
-fi
-
 # If jack was not set by the environment variable, assume it is in the path.
 if [ -z "$JACK" ]; then
   export JACK="jack"