Export header libraries to eliminate include_dirs elsewhere

This batch covers references from some test packages.

Bug: 201944383
Test: build
Change-Id: I5bbddae5b3131786f03be03d23d3ee7d7407cf14
diff --git a/media/codec2/components/base/Android.bp b/media/codec2/components/base/Android.bp
index f1669fd..8c7f8db 100644
--- a/media/codec2/components/base/Android.bp
+++ b/media/codec2/components/base/Android.bp
@@ -9,6 +9,16 @@
     default_applicable_licenses: ["frameworks_av_license"],
 }
 
+cc_library_headers {
+    name: "libcodec2_soft_common_headers",
+    defaults: ["libcodec2-impl-defaults"],
+    vendor_available: true,
+
+    export_include_dirs: [
+        "include",
+    ],
+}
+
 cc_library {
     name: "libcodec2_soft_common",
     defaults: ["libcodec2-impl-defaults"],