Mark FlutterELinuxEngine, FlutterELinuxView and FlutterELinuxTextureRegistrar

as unsafe references for importing into Swift, consolidating Swift annotation
macro wrappers into flutter_export.h.

This patch allows the importing of C++ engine APIs into Swift, using the Swift
C++ bridging layer.

Signed-off-by: Luke Howard <[email protected]>

Author: lhoward

Diff for: src/flutter/shell/platform/common/client_wrapper/include/flutter/texture_registrar.h

@@ -136,7 +136,7 @@ class TextureRegistrar {
   // Unregisters an existing texture object.
   // DEPRECATED: Use UnregisterTexture(texture_id, optional_callback) instead.
   virtual bool UnregisterTexture(int64_t texture_id) = 0;
-};
+} SWIFT_UNSAFE_REFERENCE;
 
 }  // namespace flutter
 

Diff for: src/flutter/shell/platform/common/public/flutter_export.h

@@ -25,4 +25,13 @@
 
 #endif  // FLUTTER_DESKTOP_LIBRARY
 
+#if __has_include(<swift/bridging>)
+#include <swift/bridging>
+#else
+#define SWIFT_UNSAFE_REFERENCE
+#define SWIFT_SHARED_REFERENCE(_retain, _release)
+#define SWIFT_RETURNS_RETAINED
+#define SWIFT_RETURNS_UNRETAINED
+#endif
+
 #endif  // FLUTTER_SHELL_PLATFORM_COMMON_PUBLIC_FLUTTER_EXPORT_H_

Diff for: src/flutter/shell/platform/common/public/flutter_plugin_registrar.h

@@ -24,7 +24,7 @@ typedef void (*FlutterDesktopOnPluginRegistrarDestroyed)(
     FlutterDesktopPluginRegistrarRef);
 
 // Returns the engine messenger associated with this registrar.
-FLUTTER_EXPORT FlutterDesktopMessengerRef
+FLUTTER_EXPORT SWIFT_RETURNS_UNRETAINED FlutterDesktopMessengerRef
 FlutterDesktopPluginRegistrarGetMessenger(
     FlutterDesktopPluginRegistrarRef registrar);
 

Diff for: src/flutter/shell/platform/linux_embedded/flutter_elinux_engine.h

@@ -195,7 +195,7 @@ class FlutterELinuxEngine {
   std::unique_ptr<VsyncWaiter> vsync_waiter_;
 
   bool enable_impeller_ = false;
-};
+} SWIFT_UNSAFE_REFERENCE;
 
 }  // namespace flutter
 

Diff for: src/flutter/shell/platform/linux_embedded/flutter_elinux_state.h

@@ -9,12 +9,6 @@
 #include <memory>
 #include <mutex>
 
-#if __has_include(<swift/bridging>)
-#include <swift/bridging>
-#else
-#define SWIFT_SHARED_REFERENCE(_retain, _release)
-#endif
-
 #include "flutter/shell/platform/common/client_wrapper/include/flutter/plugin_registrar.h"
 #include "flutter/shell/platform/common/incoming_message_dispatcher.h"
 #include "flutter/shell/platform/embedder/embedder.h"

Diff for: src/flutter/shell/platform/linux_embedded/flutter_elinux_view.h

@@ -318,7 +318,7 @@ class FlutterELinuxView : public WindowBindingHandlerDelegate {
   // Current view rotation (FlutterTransformation).
   FlutterTransformation view_rotation_transformation_ = {
       1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0};
-};
+} SWIFT_UNSAFE_REFERENCE;
 
 }  // namespace flutter
 

Diff for: src/flutter/shell/platform/linux_embedded/public/flutter_elinux.h

@@ -216,7 +216,7 @@ FLUTTER_EXPORT FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
     FlutterDesktopPluginRegistrarRef registrar);
 
 // Returns the messenger associated with the engine.
-FLUTTER_EXPORT FlutterDesktopMessengerRef
+FLUTTER_EXPORT SWIFT_RETURNS_UNRETAINED FlutterDesktopMessengerRef
 FlutterDesktopEngineGetMessenger(FlutterDesktopEngineRef engine);
 
 // Returns the texture registrar associated with the engine.