Use filegroup to simplify Android.bp for frameworks and its friends

Java and AIDL source files under frameworks/base are now modularized
using filegroup. Each filegroup has 'path' property set to the base
directory of the ssource files. This allows us to not rely on
aidl.[local_]include_dirs and srcs_lib_whitelist_dirs to get the base
directories.

Bug: 70046217
Test: m
Exempt-From-Owner-Approval: Approved internally
Merged-In: I0705ddf76b3c628127f65d75e0a8b06c6c250fe2
(cherry picked from commit b360931bf0f2d011dada18762829c0d0e47c54b6)
Change-Id: I0705ddf76b3c628127f65d75e0a8b06c6c250fe2
diff --git a/packages/services/Proxy/Android.bp b/packages/services/Proxy/Android.bp
index 87aa763..d93c9f8 100644
--- a/packages/services/Proxy/Android.bp
+++ b/packages/services/Proxy/Android.bp
@@ -5,3 +5,9 @@
     certificate: "platform",
     privileged: true,
 }
+
+filegroup {
+    name: "ProxyHandler-aidl-sources",
+    srcs: ["src/**/*.aidl"],
+    path: "src",
+}