Import initial work on Android frontend

android/app/src/cpp/main.cpp

@@ -0,0 +1,17 @@
+#include "core/host_interface.h"
+#include <jni.h>
+
+#define DEFINE_JNI_METHOD(return_type, name, ...)                                                                      \
+  extern "C" JNIEXPORT return_type JNICALL Java_com_github_stenzek_duckstation_##name(__VA_ARGS__)
+
+DEFINE_JNI_METHOD(bool, createSystem)
+{
+  return false;
+}
+
+DEFINE_JNI_METHOD(bool, bootSystem, const char* filename, const char* state_filename)
+{
+  return false;
+}
+
+DEFINE_JNI_METHOD(void, runFrame) {}