Remove unnecessary DartIO::EntropySource wrapper (#8635)

lib/io/dart_io.cc

@@ -21,8 +21,4 @@ void DartIO::InitForIsolate() {
   }
 }
 
-bool DartIO::EntropySource(uint8_t* buffer, intptr_t length) {
-  return dart::bin::GetEntropy(buffer, length);
-}
-
 }  // namespace flutter

lib/io/dart_io.h

@@ -14,7 +14,6 @@ namespace flutter {
 class DartIO {
  public:
   static void InitForIsolate();
-  static bool EntropySource(uint8_t* buffer, intptr_t length);
 
  private:
   FML_DISALLOW_IMPLICIT_CONSTRUCTORS(DartIO);

runtime/dart_vm.cc

@@ -383,7 +383,7 @@ DartVM::DartVM(std::shared_ptr<const DartVMData> vm_data,
         DartIsolate::DartIsolateCleanupCallback);
     params.thread_exit = ThreadExitCallback;
     params.get_service_assets = GetVMServiceAssetsArchiveCallback;
-    params.entropy_source = DartIO::EntropySource;
+    params.entropy_source = dart::bin::GetEntropy;
     char* init_error = Dart_Initialize(&params);
     if (init_error) {
       FML_LOG(FATAL) << "Error while initializing the Dart VM: " << init_error;