Set stem for uninstalled apex modules

Apex modules with installable: false are not installed, so the
dist rule copies from LOCAL_BUILT_MODULE instead of
LOCAL_INSTALLED_MODULE.  If LOCAL_BUILT_MODULE_STEM is unset,
LOCAL_BUILT_MODULE will have the module name as the stem,
resulting in an incorrect file copied to the dist directory.
Set LOCAL_MODULE_STEM instead of LOCAL_INSTALLED_MODULE_STEM,
which also covers LOCAL_BUILT_MODUL_STEM.

Fixes: 122277867
Test: tapas test1_com.android.tzdata && m dist
Change-Id: I0af0c5adcac478a1ce68c4625203fd9bd56bf94d
diff --git a/apex/apex.go b/apex/apex.go
index 6230236..71ecbdb 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -863,7 +863,7 @@
 					fmt.Fprintln(w, "LOCAL_PATH :=", moduleDir)
 					fmt.Fprintln(w, "LOCAL_MODULE :=", fi.moduleName)
 					fmt.Fprintln(w, "LOCAL_MODULE_PATH :=", filepath.Join("$(OUT_DIR)", a.installDir.RelPathString(), name, fi.installDir))
-					fmt.Fprintln(w, "LOCAL_INSTALLED_MODULE_STEM :=", fi.builtFile.Base())
+					fmt.Fprintln(w, "LOCAL_MODULE_STEM :=", fi.builtFile.Base())
 					fmt.Fprintln(w, "LOCAL_PREBUILT_MODULE_FILE :=", fi.builtFile.String())
 					fmt.Fprintln(w, "LOCAL_MODULE_CLASS :=", fi.class.NameInMake())
 					fmt.Fprintln(w, "LOCAL_UNINSTALLABLE_MODULE :=", !a.installable())
@@ -897,7 +897,7 @@
 				fmt.Fprintln(w, "LOCAL_MODULE_CLASS := ETC") // do we need a new class?
 				fmt.Fprintln(w, "LOCAL_PREBUILT_MODULE_FILE :=", a.outputFiles[apexType].String())
 				fmt.Fprintln(w, "LOCAL_MODULE_PATH :=", filepath.Join("$(OUT_DIR)", a.installDir.RelPathString()))
-				fmt.Fprintln(w, "LOCAL_INSTALLED_MODULE_STEM :=", name+apexType.suffix())
+				fmt.Fprintln(w, "LOCAL_MODULE_STEM :=", name+apexType.suffix())
 				fmt.Fprintln(w, "LOCAL_UNINSTALLABLE_MODULE :=", !a.installable())
 				fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES :=", String(a.properties.Key))
 				fmt.Fprintln(w, "include $(BUILD_PREBUILT)")