fakehwc, libvr_hwc-hal: ComposerBase is moved

ComposerBase is moved to another library and is renamed to
ComposerHal.

Test: builds
Change-Id: Ie9159b9d83558587d75aa6d0ad89a1848a281d01
diff --git a/services/vr/hardware_composer/Android.bp b/services/vr/hardware_composer/Android.bp
index caf9049..5555793 100644
--- a/services/vr/hardware_composer/Android.bp
+++ b/services/vr/hardware_composer/Android.bp
@@ -33,6 +33,11 @@
 
   header_libs: [
     "android.hardware.graphics.composer@2.1-command-buffer",
+    "android.hardware.graphics.composer@2.1-hal",
+  ],
+
+  export_header_lib_headers: [
+    "android.hardware.graphics.composer@2.1-hal",
   ],
 
   export_static_lib_headers: [