Fix custom FlValue API not being exported (#51154)

Would fail to link when using it in a Flutter app.

Author: robert-ancell

shell/platform/linux/fl_standard_message_codec.cc

@@ -639,9 +639,10 @@ G_MODULE_EXPORT FlStandardMessageCodec* fl_standard_message_codec_new() {
       g_object_new(fl_standard_message_codec_get_type(), nullptr));
 }
 
-void fl_standard_message_codec_write_size(FlStandardMessageCodec* codec,
-                                          GByteArray* buffer,
-                                          uint32_t size) {
+G_MODULE_EXPORT void fl_standard_message_codec_write_size(
+    FlStandardMessageCodec* codec,
+    GByteArray* buffer,
+    uint32_t size) {
   if (size < 254) {
     write_uint8(buffer, size);
   } else if (size <= 0xffff) {
@@ -653,11 +654,12 @@ void fl_standard_message_codec_write_size(FlStandardMessageCodec* codec,
   }
 }
 
-gboolean fl_standard_message_codec_read_size(FlStandardMessageCodec* codec,
-                                             GBytes* buffer,
-                                             size_t* offset,
-                                             uint32_t* value,
-                                             GError** error) {
+G_MODULE_EXPORT gboolean fl_standard_message_codec_read_size(
+    FlStandardMessageCodec* codec,
+    GBytes* buffer,
+    size_t* offset,
+    uint32_t* value,
+    GError** error) {
   uint8_t value8;
   if (!read_uint8(buffer, offset, &value8, error)) {
     return FALSE;
@@ -680,18 +682,20 @@ gboolean fl_standard_message_codec_read_size(FlStandardMessageCodec* codec,
   return TRUE;
 }
 
-gboolean fl_standard_message_codec_write_value(FlStandardMessageCodec* self,
-                                               GByteArray* buffer,
-                                               FlValue* value,
-                                               GError** error) {
+G_MODULE_EXPORT gboolean fl_standard_message_codec_write_value(
+    FlStandardMessageCodec* self,
+    GByteArray* buffer,
+    FlValue* value,
+    GError** error) {
   return FL_STANDARD_MESSAGE_CODEC_GET_CLASS(self)->write_value(self, buffer,
                                                                 value, error);
 }
 
-FlValue* fl_standard_message_codec_read_value(FlStandardMessageCodec* self,
-                                              GBytes* buffer,
-                                              size_t* offset,
-                                              GError** error) {
+G_MODULE_EXPORT FlValue* fl_standard_message_codec_read_value(
+    FlStandardMessageCodec* self,
+    GBytes* buffer,
+    size_t* offset,
+    GError** error) {
   uint8_t type;
   if (!read_uint8(buffer, offset, &type, error)) {
     return nullptr;

shell/platform/linux/fl_value.cc

@@ -371,9 +371,9 @@ G_MODULE_EXPORT FlValue* fl_value_new_map() {
   return reinterpret_cast<FlValue*>(self);
 }
 
-FlValue* fl_value_new_custom(int type,
-                             gconstpointer value,
-                             GDestroyNotify destroy_notify) {
+G_MODULE_EXPORT FlValue* fl_value_new_custom(int type,
+                                             gconstpointer value,
+                                             GDestroyNotify destroy_notify) {
   FlValueCustom* self = reinterpret_cast<FlValueCustom*>(
       fl_value_new(FL_VALUE_TYPE_CUSTOM, sizeof(FlValueCustom)));
   self->type = type;
@@ -382,11 +382,12 @@ FlValue* fl_value_new_custom(int type,
   return reinterpret_cast<FlValue*>(self);
 }
 
-FlValue* fl_value_new_custom_object(int type, GObject* object) {
+G_MODULE_EXPORT FlValue* fl_value_new_custom_object(int type, GObject* object) {
   return fl_value_new_custom(type, g_object_ref(object), g_object_unref);
 }
 
-FlValue* fl_value_new_custom_object_take(int type, GObject* object) {
+G_MODULE_EXPORT FlValue* fl_value_new_custom_object_take(int type,
+                                                         GObject* object) {
   return fl_value_new_custom(type, object, g_object_unref);
 }
 

shell/platform/linux/public/flutter_linux/fl_binary_messenger.h

@@ -32,6 +32,7 @@ typedef enum {
   FL_BINARY_MESSENGER_ERROR_ALREADY_RESPONDED,
 } FlBinaryMessengerError;
 
+G_MODULE_EXPORT
 GQuark fl_binary_messenger_codec_error_quark(void) G_GNUC_CONST;
 
 G_MODULE_EXPORT

shell/platform/linux/public/flutter_linux/fl_json_message_codec.h

@@ -34,6 +34,7 @@ typedef enum {
   // NOLINTEND(readability-identifier-naming)
 } FlJsonMessageCodecError;
 
+G_MODULE_EXPORT
 GQuark fl_json_message_codec_error_quark(void) G_GNUC_CONST;
 
 G_MODULE_EXPORT

shell/platform/linux/public/flutter_linux/fl_message_codec.h

@@ -38,6 +38,7 @@ typedef enum {
   // NOLINTEND(readability-identifier-naming)
 } FlMessageCodecError;
 
+G_MODULE_EXPORT
 GQuark fl_message_codec_error_quark(void) G_GNUC_CONST;
 
 G_MODULE_EXPORT

shell/platform/linux/public/flutter_linux/fl_method_response.h

@@ -37,6 +37,7 @@ typedef enum {
   // NOLINTEND(readability-identifier-naming)
 } FlMethodResponseError;
 
+G_MODULE_EXPORT
 GQuark fl_method_response_error_quark(void) G_GNUC_CONST;
 
 G_MODULE_EXPORT