Update package names to work with the proto3 compiler

Bug: b/28974522
Change-Id: I5f3adf4946ee4ba1e09e4f40afe83c151405972a
diff --git a/tools/aapt2/compile/Compile.cpp b/tools/aapt2/compile/Compile.cpp
index a06140c..f0b18e6 100644
--- a/tools/aapt2/compile/Compile.cpp
+++ b/tools/aapt2/compile/Compile.cpp
@@ -482,7 +482,9 @@
 
   void BackUp(int count) override { buffer_->BackUp(count); }
 
-  int64_t ByteCount() const override { return buffer_->size(); }
+  google::protobuf::int64 ByteCount() const override {
+    return buffer_->size();
+  }
 
   bool HadError() const override { return false; }