Gate unittests on USE_TCORE_WL too

The unittests cc files unconditionally include <tizen_core_wl.h>
and call tizen_core_wl_init(), which breaks ecore builds because
the header is not in the include path on non-tcore sysroots.
Conversely, the flutter_tizen_unittests executable target was
not getting the USE_TCORE_WL define, so a tcore build was pulling
in flutter_tizen_engine.h -> tizen_view_base.h -> the ecore
input-method header.

- Add #ifdef USE_TCORE_WL gates in
  flutter_tizen_engine_unittest.cc and
  flutter_tizen_texture_registrar_unittests.cc so each variant
  uses the matching init call (tizen_core_wl_init / ecore_init).
- Propagate USE_TCORE_WL to the flutter_tizen_unittests target
  in BUILD.gn when use_tcore is set.

Author: JSUYA

flutter/shell/platform/tizen/BUILD.gn

@@ -297,6 +297,10 @@ executable("flutter_tizen_unittests") {
 
   ldflags = [ "-Wl,--unresolved-symbols=ignore-in-shared-libs" ]
 
+  if (use_tcore) {
+    defines = [ "USE_TCORE_WL" ]
+  }
+
   configs += [ ":flutter_tizen_config" ]
 
   deps += [

flutter/shell/platform/tizen/flutter_tizen_engine_unittest.cc

@@ -4,7 +4,11 @@
 
 #include "flutter/shell/platform/tizen/flutter_tizen_engine.h"
 
+#ifdef USE_TCORE_WL
 #include <tizen_core_wl.h>
+#else
+#include <Ecore.h>
+#endif
 
 #include "flutter/shell/platform/embedder/test_utils/proc_table_replacement.h"
 #include "flutter/shell/platform/tizen/testing/engine_modifier.h"
@@ -15,7 +19,13 @@ namespace testing {
 
 class FlutterTizenEngineTest : public ::testing::Test {
  public:
-  FlutterTizenEngineTest() { tizen_core_wl_init(); }
+  FlutterTizenEngineTest() {
+#ifdef USE_TCORE_WL
+    tizen_core_wl_init();
+#else
+    ecore_init();
+#endif
+  }
 
  protected:
   void SetUp() {

flutter/shell/platform/tizen/flutter_tizen_texture_registrar_unittests.cc

@@ -4,7 +4,11 @@
 
 #include "flutter/shell/platform/tizen/flutter_tizen_texture_registrar.h"
 
+#ifdef USE_TCORE_WL
 #include <tizen_core_wl.h>
+#else
+#include <Ecore.h>
+#endif
 
 #include <iostream>
 
@@ -18,7 +22,13 @@ namespace testing {
 
 class FlutterTizenTextureRegistrarTest : public ::testing::Test {
  public:
-  FlutterTizenTextureRegistrarTest() { tizen_core_wl_init(); }
+  FlutterTizenTextureRegistrarTest() {
+#ifdef USE_TCORE_WL
+    tizen_core_wl_init();
+#else
+    ecore_init();
+#endif
+  }
 
  protected:
   void SetUp() {