Add a source_module_name to android_app

For multiple mainline prebuilts, we will have multiple versioned
prebuilt apps in the tree. The soong name of these prebuilts will have a
version prefix to prevent name collisions (e.g. MyGoogleApp.v2).

This CL introduces a source_module_name property in android_app_imoprt.
This property will be used for the following
1. Determining installation path. This should be
/system/app/MyGoogleApp/MyGoogleApp.apk
and not
/system/app/MyGoogleApp.v2/MyGoogleApp.apk
(filename prop determines the filename and not the dir name)

2. Preventing duplicate installation rules: This property will be used
   to create a dependency to the source app, and call HideFromMake on
   all the unflagged apps

Test: presubmits
Test: locally # Created CaptivePortalLoginGoogle.v2 and selected it
using one of the RELEASE_APEX_CONTRIBUTION_* flags

Bug: 326995930
Change-Id: If4ab9f9bd295117c96eb062cf3b3d2efc8bfed12
diff --git a/java/app_import.go b/java/app_import.go
index 8c90e4c..dc84fc2 100644
--- a/java/app_import.go
+++ b/java/app_import.go
@@ -145,6 +145,11 @@
 	// Whether or not to skip checking the preprocessed apk for proper alignment and uncompressed
 	// JNI libs and dex files. Default is false
 	Skip_preprocessed_apk_checks *bool
+
+	// Name of the source soong module that gets shadowed by this prebuilt
+	// If unspecified, follows the naming convention that the source module of
+	// the prebuilt is Name() without "prebuilt_" prefix
+	Source_module_name *string
 }
 
 func (a *AndroidAppImport) IsInstallable() bool {
@@ -274,6 +279,10 @@
 	return a.BaseModuleName()
 }
 
+func (a *AndroidAppImport) BaseModuleName() string {
+	return proptools.StringDefault(a.properties.Source_module_name, a.ModuleBase.Name())
+}
+
 func (a *AndroidAppImport) generateAndroidBuildActions(ctx android.ModuleContext) {
 	if a.Name() == "prebuilt_framework-res" {
 		ctx.ModuleErrorf("prebuilt_framework-res found. This used to have special handling in soong, but was removed due to prebuilt_framework-res no longer existing. This check is to ensure it doesn't come back without readding the special handling.")