gn2bp: Set --cc-out-dir arg for protoc_wrapper.py

Test: ./update_result.sh
Change-Id: I7a90c66178cd6cfb01d7733f4da7b8eb5485c767
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index 4286c62..a0cdb6c 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -871,6 +871,8 @@
         # Adjusting path for net_quic_proto_gen
         if target.name == "//net/third_party/quiche:net_quic_proto_gen":
           target.args[i + 1] += '/../../../../'
+      elif val == '--cc-out-dir':
+        target.args[i + 1] = re.sub('^gen', '$(genDir)', target.args[i + 1])
 
   script = gn_utils.label_to_path(target.script)
   module.tool_files.add(script)