Add wmediumd proto java library rule

Bug: 273384914
Test: cvd start && atest WmediumdControlE2eTest
Change-Id: I01ecb6bfbe3f744f7e6357314173ed1476d151c4
diff --git a/Android.bp b/Android.bp
index de1b8cf..f757884 100644
--- a/Android.bp
+++ b/Android.bp
@@ -90,6 +90,23 @@
     ],
 }
 
+java_library_host {
+    name: "WmediumdServerProto_java",
+    srcs: [
+        ":WmediumdServerProto",
+    ],
+    static_libs: [
+        "libprotobuf-java-full",
+    ],
+    proto: {
+        canonical_path_from_root: false,
+        type: "full",
+        include_dirs: [
+            "external/protobuf/src",
+        ],
+    },
+}
+
 cc_binary_host {
     name: "wmediumd",
     srcs: [
diff --git a/wmediumd_server/wmediumd.proto b/wmediumd_server/wmediumd.proto
index fe354b5..0c45655 100644
--- a/wmediumd_server/wmediumd.proto
+++ b/wmediumd_server/wmediumd.proto
@@ -16,6 +16,8 @@
 
 package wmediumdserver;
 
+option java_package = "com.android.wmediumd";
+
 import "google/protobuf/empty.proto";
 
 service WmediumdService {