Revert "Use Kernel frontend from run_vm_tests."

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index 3ba45fa7e66d604b8a80e3da71ba334703640cac..300fe57e1a3d6a998f8627adbce2bbb0dcef93dc 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -6045,21 +6045,6 @@ Dart_CompileToKernel(const char* script_uri) {
 #endif
 }
 
-DART_EXPORT Dart_KernelCompilationResult
-Dart_CompileSourcesToKernel(const char* script_uri,
-                            int source_files_count,
-                            Dart_SourceFile sources[]) {
-#ifdef DART_PRECOMPILED_RUNTIME
-  Dart_KernelCompilationResult result;
-  result.status = Dart_KernelCompilationStatus_Unknown;
-  result.error = strdup("Dart_CompileSourcesToKernel is unsupported.");
-  return result;
-#else
-  return KernelIsolate::CompileToKernel(script_uri, source_files_count,
-                                        sources);
-#endif
-}
-
 // --- Service support ---
 
 DART_EXPORT bool Dart_IsServiceIsolate(Dart_Isolate isolate) {