Allow cc_genrule srcs to vary by architecture

Add arch_variant to the genrule srcs property so that cc_genrule
modules can vary the srcs and outs by architecture.

Test: cc/genrule_test.go
Change-Id: Idb17013e137d7ca21ca4cfc3e4c1fa7d89977043
diff --git a/genrule/genrule.go b/genrule/genrule.go
index 2824e49..e6c6efd 100644
--- a/genrule/genrule.go
+++ b/genrule/genrule.go
@@ -87,7 +87,7 @@
 	Export_include_dirs []string
 
 	// list of input files
-	Srcs []string
+	Srcs []string `android:"arch_variant"`
 }
 
 type Module struct {
@@ -504,7 +504,7 @@
 
 type genRuleProperties struct {
 	// names of the output files that will be generated
-	Out []string
+	Out []string `android:"arch_variant"`
 }
 
 var Bool = proptools.Bool
diff --git a/genrule/genrule_test.go b/genrule/genrule_test.go
index 7e16ce1..a99fa18 100644
--- a/genrule/genrule_test.go
+++ b/genrule/genrule_test.go
@@ -27,7 +27,7 @@
 
 func setUp() {
 	var err error
-	buildDir, err = ioutil.TempDir("", "soong_java_test")
+	buildDir, err = ioutil.TempDir("", "genrule_test")
 	if err != nil {
 		panic(err)
 	}