Bind Win32 main-thread queue to runtime state

src/platform_windows/windows_runtime_state.cpp

@@ -3,6 +3,7 @@
 #include "platform_windows/windows_runtime_state.h"
 
 #include "app.h"
+#include "app_runtime.h"
 #include "wacom.h"
 
 namespace pp::platform::windows {
@@ -10,6 +11,7 @@ namespace {
 
 struct RetainedWindowsRuntimeState final {
     std::unique_ptr<App> owned_app;
+    AppRuntime* runtime = nullptr;
     WacomTablet tablet;
 };
 
@@ -31,4 +33,14 @@ WacomTablet& retained_wacom_tablet() noexcept
     return retained_runtime_state().tablet;
 }
 
+AppRuntime* retained_bound_runtime() noexcept
+{
+    return retained_runtime_state().runtime;
+}
+
+void bind_runtime(AppRuntime* runtime) noexcept
+{
+    retained_runtime_state().runtime = runtime;
+}
+
 }