Add dist support to Soong

When dist'ing a library or binary that has use_version_lib set, always
distribute the stamped version, even for the device.

Test: m test_build_version_test dist
Change-Id: I2995ec516b1d182ce18f099aeaa4d186ffbcf01f
diff --git a/cc/androidmk.go b/cc/androidmk.go
index 5e38973..f5e04bb 100644
--- a/cc/androidmk.go
+++ b/cc/androidmk.go
@@ -151,6 +151,7 @@
 		ret.Class = "HEADER_LIBRARIES"
 	}
 
+	ret.DistFile = library.distFile
 	ret.Extra = append(ret.Extra, func(w io.Writer, outputFile android.Path) {
 		library.androidMkWriteExportedFlags(w)
 		fmt.Fprintln(w, "LOCAL_ADDITIONAL_DEPENDENCIES := ")
@@ -194,6 +195,7 @@
 	ctx.subAndroidMk(ret, binary.baseInstaller)
 
 	ret.Class = "EXECUTABLES"
+	ret.DistFile = binary.distFile
 	ret.Extra = append(ret.Extra, func(w io.Writer, outputFile android.Path) {
 		fmt.Fprintln(w, "LOCAL_SOONG_UNSTRIPPED_BINARY :=", binary.unstrippedOutputFile.String())
 		if len(binary.symlinks) > 0 {