ART: Enable build options in test runner script.

Adds a --build-option which passes an argument through to the build
script.

Fixes propagation of dx options.

Test: manual use of run-test script
Change-Id: I04ebfeda05fecfe8ac1ad91762d8330db5834fbe
diff --git a/test/run-test b/test/run-test
index e808dee..6134a14 100755
--- a/test/run-test
+++ b/test/run-test
@@ -247,6 +247,11 @@
         option="$1"
         run_args="${run_args} -Xcompiler-option $option"
         shift
+    elif [ "x$1" = "x--build-option" ]; then
+        shift
+        option="$1"
+        build_args="${build_args} $option"
+        shift
     elif [ "x$1" = "x--runtime-option" ]; then
         shift
         option="$1"
@@ -611,6 +616,7 @@
         echo "  Runtime Options:"
         echo "    -O                    Run non-debug rather than debug build (off by default)."
         echo "    -Xcompiler-option     Pass an option to the compiler."
+        echo "    --build-option        Pass an option to the build script."
         echo "    --runtime-option      Pass an option to the runtime."
         echo "    --debug               Wait for a debugger to attach."
         echo "    --debuggable          Whether to compile Java code for a debugger."