Cleanup app snapshots on isolate/vm exit.

runtime/bin/extensions_fuchsia.cc

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_FUCHSIA)
 
 #include "bin/extensions.h"
 #include <dlfcn.h>  // NOLINT
 
+#include "platform/assert.h"
+
 namespace dart {
 namespace bin {
 
 const char* kVmSnapshotDataSymbolName = "_kDartVmSnapshotData";
 const char* kVmSnapshotInstructionsSymbolName = "_kDartVmSnapshotInstructions";
 const char* kIsolateSnapshotDataSymbolName = "_kDartIsolateSnapshotData";
 const char* kIsolateSnapshotInstructionsSymbolName =
     "_kDartIsolateSnapshotInstructions";
 
-void* Extensions::LoadExtensionLibrary(const char* library_file) {
+void* Extensions::LoadLibrary(const char* library_file) {
   return dlopen(library_file, RTLD_LAZY);
 }
 
+
 void* Extensions::ResolveSymbol(void* lib_handle, const char* symbol) {
   dlerror();
   return dlsym(lib_handle, symbol);
 }
 
+
+void Extensions::UnloadLibrary(void* lib_handle) {
+  dlerror();
+  int result = dlclose(lib_handle);
+  ASSERT(result == 0);
+}
+
+
 Dart_Handle Extensions::GetError() {
   const char* err_str = dlerror();
   if (err_str != NULL) {
     return Dart_NewApiError(err_str);
   }
   return Dart_Null();
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_FUCHSIA)