Remove LSAN supressions for Linux embedder (#56913)

Fixes flutter/flutter#90155

Author: robert-ancell

shell/platform/linux/fl_basic_message_channel_test.cc

@@ -43,7 +43,7 @@ TEST(FlBasicMessageChannelTest, SendMessageWithoutResponse) {
             g_bytes_new(message->message, message->message_size);
         g_autoptr(FlStandardMessageCodec) codec =
             fl_standard_message_codec_new();
-        FlValue* message_value = fl_message_codec_decode_message(
+        g_autoptr(FlValue) message_value = fl_message_codec_decode_message(
             FL_MESSAGE_CODEC(codec), message_bytes, nullptr);
         EXPECT_EQ(fl_value_get_type(message_value), FL_VALUE_TYPE_STRING);
         EXPECT_STREQ(fl_value_get_string(message_value), "Hello World!");

shell/platform/linux/fl_key_event_channel.cc

@@ -109,13 +109,13 @@ gboolean fl_key_event_channel_send_finish(GObject* object,
                                           GAsyncResult* result,
                                           gboolean* handled,
                                           GError** error) {
-  FlValue* message = fl_basic_message_channel_send_finish(
+  g_autoptr(FlValue) message = fl_basic_message_channel_send_finish(
       FL_BASIC_MESSAGE_CHANNEL(object), result, error);
   if (message == nullptr) {
     return FALSE;
   }
 
-  g_autoptr(FlValue) handled_value = fl_value_lookup_string(message, "handled");
+  FlValue* handled_value = fl_value_lookup_string(message, "handled");
   *handled = fl_value_get_bool(handled_value);
 
   return TRUE;

testing/lsan_suppressions.txt

@@ -50,12 +50,6 @@ leak:RefCountedTest_DebugChecks_Test::TestBody
 # and allow some tests to inspect contents.
 leak:*flutter/shell/platform/linux/testing/mock_engine.cc
 
-# TODO(bdero): Fix FL leaks: https://github.com/flutter/flutter/issues/90155
-leak:*flutter/shell/platform/linux/fl_keyboard_handler_test.cc*
-leak:*flutter/shell/platform/linux/fl_key_channel_responder_test.cc*
-leak:*flutter/shell/platform/linux/fl_basic_message_channel_test.cc*
-leak:fl_message_codec_decode_message
-
 # TODO(bdero): https://github.com/flutter/flutter/issues/90156
 # Unfortunately, realloc calls originating from g_realloc effectively obscure
 # the trace of the original allocation. Deeper investigation is required to