Separate sdk member type functionality into its own file

Bug: 195754365
Test: m nothing
Change-Id: I63effd8dbcb984d144daf266e53d33a0d07224e4
diff --git a/sdk/Android.bp b/sdk/Android.bp
index 368c03a..0c9bf27 100644
--- a/sdk/Android.bp
+++ b/sdk/Android.bp
@@ -16,6 +16,7 @@
     srcs: [
         "bp.go",
         "exports.go",
+        "member_type.go",
         "sdk.go",
         "update.go",
     ],