Add FeatureFlag for Virtual AB Compression

Test: treehugger
Bug: 168554689
Change-Id: I732cd1ef55c5c4362ef88a640c2ca228f472af89
diff --git a/common/dynamic_partition_control_stub.h b/common/dynamic_partition_control_stub.h
index 94dba1b..8bff474 100644
--- a/common/dynamic_partition_control_stub.h
+++ b/common/dynamic_partition_control_stub.h
@@ -31,6 +31,7 @@
  public:
   FeatureFlag GetDynamicPartitionsFeatureFlag() override;
   FeatureFlag GetVirtualAbFeatureFlag() override;
+  FeatureFlag GetVirtualAbCompressionFeatureFlag() override;
   bool OptimizeOperation(const std::string& partition_name,
                          const InstallOperation& operation,
                          InstallOperation* optimized) override;