Jarjar com.google.protobuf

This avoids potential conflicts if the library is also added to the
bootclasspath.

com.google.protobuf is pulled as a dependency when adding protobuffers,
like those used for data stall, IP provisioning and validation metrics.

Bug: 159587267
Test: m; manual: booted, wifi working

Change-Id: I3339e47c1ca1cd8b0186da0dbf880eff245b4c67
diff --git a/jarjar-rules-shared.txt b/jarjar-rules-shared.txt
index c4f4602..438fc61 100644
--- a/jarjar-rules-shared.txt
+++ b/jarjar-rules-shared.txt
@@ -2,6 +2,7 @@
 rule com.android.net.module.util.** com.android.networkstack.util.@1
 
 rule com.android.internal.util.** android.net.networkstack.util.@1
+rule com.google.protobuf.** com.android.networkstack.protobuf.@1
 
 # Classes from net-utils-framework-common
 rule com.android.net.module.util.** com.android.networkstack.util.@1