Create product variant for product partition

When PRODUCT_PRODUCT_VNDK_VERSION is set to 'current', product
modules are enforced to use only VNDK libs from the system partition
as BOARD_VNDK_VERSION does to vendor partition.

Modules with 'vendor_available: true' create product variant as well
as core and vendor variants. The product variant as an image variant
is used for the modules in /product or /system/product.

It must not affect the current build behavior without
PRODUCT_PRODUCT_VNDK_VERSION set.

Bug: 134099726
Bug: 138966004
Bug: 144534640
Test: build without PRODUCT_PRODUCT_VNDK_VERSION set
Change-Id: I4d3585c110d84493e45bf76d550dc240bb26137f
diff --git a/cc/installer.go b/cc/installer.go
index 9fdc88a..2f55ac5 100644
--- a/cc/installer.go
+++ b/cc/installer.go
@@ -72,7 +72,11 @@
 		dir = filepath.Join(dir, ctx.Arch().ArchType.String())
 	}
 	if installer.location == InstallInData && ctx.useVndk() {
-		dir = filepath.Join(dir, "vendor")
+		if ctx.inProduct() {
+			dir = filepath.Join(dir, "product")
+		} else {
+			dir = filepath.Join(dir, "vendor")
+		}
 	}
 	return android.PathForModuleInstall(ctx, dir, installer.subDir,
 		installer.relativeInstallPath(), installer.relative)