Use conventional args style for gen_jarjar

gen_jarjar supported multi-valued arguments via space-separated lists,
like "--apistubs foo bar". This is unusual, as "bar" would generally be
interpreted as a positional argument instead.

Change the usage to "--apistubs foo --apistubs bar", which is more
conventional. Also remove the "--jars" switch to have the jars be
positional arguments instead, and change the "--unsupportedapi"
arguments to be a column-separated list (like java classpath), instead
of space-separated. For --unsupportedapi, this allows providing a list
of files via minimal modifications in the genrule usage.

Test: m
Change-Id: Id67ad16de2ea6682fee402540f464ed3b5b0cca9
diff --git a/framework/Android.bp b/framework/Android.bp
index fcce7a5..485961c 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -228,12 +228,13 @@
     ],
     out: ["framework_connectivity_jarjar_rules.txt"],
     cmd: "$(location jarjar-rules-generator) " +
-        "--jars $(location :framework-connectivity-pre-jarjar{.jar}) " +
+        "$(location :framework-connectivity-pre-jarjar{.jar}) " +
         "$(location :framework-connectivity-t-pre-jarjar{.jar}) " +
         "--prefix android.net.connectivity " +
         "--apistubs $(location :framework-connectivity.stubs.module_lib{.jar}) " +
-        "$(location :framework-connectivity-t.stubs.module_lib{.jar}) " +
-        "--unsupportedapi $(locations :connectivity-hiddenapi-files) " +
+        "--apistubs $(location :framework-connectivity-t.stubs.module_lib{.jar}) " +
+        // Make a ":"-separated list. There will be an extra ":" but empty items are ignored.
+        "--unsupportedapi $$(printf ':%s' $(locations :connectivity-hiddenapi-files)) " +
         "--excludes $(location jarjar-excludes.txt) " +
         "--output $(out)",
     visibility: [