Support .rs and .fs files in cc_* module srcs lists

Translate .rs and .fs files to .cpp files using llvm-rs-cc.

Test: builds
Change-Id: I242cea0d09c9985730a512cec7705c3f1479f4ed

cc/config/global.go

@@ -151,6 +151,12 @@ func init() {
 	pctx.StaticVariable("RSLLVMPrebuiltsPath", "${RSClangBase}/${HostPrebuiltTag}/${RSClangVersion}/bin")
 	pctx.StaticVariable("RSIncludePath", "${RSLLVMPrebuiltsPath}/../lib64/clang/${RSReleaseVersion}/include")
 
+	pctx.PrefixedPathsForOptionalSourceVariable("RsGlobalIncludes", "-I",
+		[]string{
+			"external/clang/lib/Headers",
+			"frameworks/rs/script_api/include",
+		})
+
 	pctx.VariableFunc("CcWrapper", func(config interface{}) (string, error) {
 		if override := config.(android.Config).Getenv("CC_WRAPPER"); override != "" {
 			return override + " ", nil