codegen: do not assume arch is arm64

Replace hard-coded path to CodegenTests.apk, which assumes the current
architechure is arm64, with dynamic lookup.

Test: manual (runTest.sh works on the aosp_x86_64-eng emulator)
Change-Id: I4110083f055a65375de89da95fdc07739a3d9da5
diff --git a/tests/Codegen/runTest.sh b/tests/Codegen/runTest.sh
index 01522735..5f03b5f 100755
--- a/tests/Codegen/runTest.sh
+++ b/tests/Codegen/runTest.sh
@@ -16,7 +16,7 @@
         header_and_eval codegen $ANDROID_BUILD_TOP/frameworks/base/tests/Codegen/src/com/android/codegentest/ParcelAllTheThingsDataClass.java && \
         cd $ANDROID_BUILD_TOP &&
         header_and_eval mmma -j16 frameworks/base/tests/Codegen && \
-        header_and_eval adb install -r -t $ANDROID_PRODUCT_OUT/testcases/CodegenTests/arm64/CodegenTests.apk && \
+        header_and_eval adb install -r -t "$(find $ANDROID_TARGET_OUT_TESTCASES -name 'CodegenTests.apk')" && \
         # header_and_eval adb shell am set-debug-app -w com.android.codegentest && \
         header_and_eval adb shell am instrument -w -e package com.android.codegentest com.android.codegentest/androidx.test.runner.AndroidJUnitRunner