Make apex modules support tagged dists

Bug: 172951145
Test: m dist my_dist_target (with patch in bug)
Change-Id: I0da4568a49ea48efbf864614a7e7c647f251a7ce
diff --git a/apex/androidmk.go b/apex/androidmk.go
index ee8b2b3..993260c 100644
--- a/apex/androidmk.go
+++ b/apex/androidmk.go
@@ -307,6 +307,7 @@
 
 func (a *apexBundle) androidMkForType() android.AndroidMkData {
 	return android.AndroidMkData{
+		DistFiles: a.distFiles,
 		Custom: func(w io.Writer, name, prefix, moduleDir string, data android.AndroidMkData) {
 			moduleNames := []string{}
 			apexType := a.properties.ApexType
@@ -391,6 +392,9 @@
 					fmt.Fprintf(w, "$(call dist-for-goals,%s,%s:%s)\n",
 						goal, a.installedFilesFile.String(), distFile)
 				}
+				for _, dist := range data.Entries.GetDistForGoals(a) {
+					fmt.Fprintf(w, dist)
+				}
 			}
 		}}
 }