Remove unneeded build files

Also make run-test default to assuming java8 language source.

Test: mma -j40 test-art-host
Test: ./test/run-test --host --build-with-javac-dx 001-HelloWorld
Change-Id: Id10b0539d919802985a373b1720534735c32434b
diff --git a/test/etc/default-build b/test/etc/default-build
index 5ba685c..d94968f 100755
--- a/test/etc/default-build
+++ b/test/etc/default-build
@@ -73,7 +73,7 @@
 JACK_EXPERIMENTAL_ARGS["default-methods"]="-D jack.java.source.version=1.8 -D jack.android.min-api-level=24"
 JACK_EXPERIMENTAL_ARGS["lambdas"]="-D jack.java.source.version=1.8 -D jack.android.min-api-level=24"
 JACK_EXPERIMENTAL_ARGS["method-handles"]="-D jack.java.source.version=1.7 -D jack.android.min-api-level=o-b1"
-JACK_EXPERIMENTAL_ARGS["java-8"]="-D jack.java.source.version=1.8 -D jack.android.min-api-level=24"
+JACK_EXPERIMENTAL_ARGS[${DEFAULT_EXPERIMENT}]="-D jack.java.source.version=1.8 -D jack.android.min-api-level=24"
 
 declare -A SMALI_EXPERIMENTAL_ARGS
 SMALI_EXPERIMENTAL_ARGS["default-methods"]="--api-level 24"
@@ -84,6 +84,7 @@
 JAVAC_EXPERIMENTAL_ARGS["default-methods"]="-source 1.8 -target 1.8"
 JAVAC_EXPERIMENTAL_ARGS["lambdas"]="-source 1.8 -target 1.8"
 JAVAC_EXPERIMENTAL_ARGS["method-handles"]="-source 1.8 -target 1.8"
+# We need to leave javac at default 1.7 so that dx will continue to work
 JAVAC_EXPERIMENTAL_ARGS[${DEFAULT_EXPERIMENT}]="-source 1.7 -target 1.7"
 JAVAC_EXPERIMENTAL_ARGS["agents"]="-source 1.8 -target 1.8"