Load updated drivers using derived loader namespace

Bug: 33531483
Test: Launch vulkan apps w/ and w/o updated driver package
Change-Id: Ia73e1e33b637d6ffd96ea0480ed6d85b9f68dce3
diff --git a/include/gui/GraphicsEnv.h b/include/gui/GraphicsEnv.h
index 9f26c14..0d3843b 100644
--- a/include/gui/GraphicsEnv.h
+++ b/include/gui/GraphicsEnv.h
@@ -19,6 +19,8 @@
 
 #include <string>
 
+struct android_namespace_t;
+
 namespace android {
 
 class GraphicsEnv {
@@ -31,10 +33,12 @@
     // in the search path must have a '!' after the zip filename, e.g.
     //     /data/app/com.example.driver/base.apk!/lib/arm64-v8a
     void setDriverPath(const std::string path);
+    android_namespace_t* getDriverNamespace();
 
 private:
     GraphicsEnv() = default;
     std::string mDriverPath;
+    android_namespace_t* mDriverNamespace = nullptr;
 };
 
 } // namespace android