Set path property for filegroup modules

The path property specifies the base directory for Java files. This can
be used by the build system to filter (or filter-out) Java files by
their package names.

Bug: 135922046
Test: m
Change-Id: I6bece92e702b560e53bc087b5960bff577dc3175
diff --git a/media/Android.bp b/media/Android.bp
index 29064ad..ef32239 100644
--- a/media/Android.bp
+++ b/media/Android.bp
@@ -67,6 +67,7 @@
         "apex/java/android/media/Session2Link.java",
         "apex/java/android/media/Session2Token.java",
     ],
+    path: "apex/java",
 }
 
 filegroup {
@@ -79,6 +80,7 @@
         "apex/java/android/media/IMediaSession2.aidl",
         "apex/java/android/media/IMediaSession2Service.aidl",
     ],
+    path: "apex/java",
 }
 
 filegroup {
@@ -98,6 +100,7 @@
         "apex/java/android/media/BufferingParams.java",
         "apex/java/android/media/ProxyDataSourceCallback.java",
     ],
+    path: "apex/java",
 }
 
 metalava_updatable_media_args = " --error UnhiddenSystemApi " +