Significantly cleans up the ImageWriter Operation class and subclasses.

chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc

Index: chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc
diff --git a/chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc b/chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc
index 23537a1b3e6d0ab0df1f810f36aff3ddc1e50086..94b267570fe0648885c2d2c7e36335914cfa5e20 100644
--- a/chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc
+++ b/chrome/browser/extensions/api/image_writer_private/destroy_partitions_operation.cc
@@ -18,18 +18,11 @@ DestroyPartitionsOperation::DestroyPartitionsOperation(
     base::WeakPtr<OperationManager> manager,
     const ExtensionId& extension_id,
     const std::string& storage_unit_id)
-    : Operation(manager, extension_id, storage_unit_id) {
-  verify_write_ = false;
-}
+    : Operation(manager, extension_id, storage_unit_id) {}
 
 DestroyPartitionsOperation::~DestroyPartitionsOperation() {}
 
-void DestroyPartitionsOperation::Start() {
-  if (!temp_dir_.CreateUniqueTempDir()) {
-    Error(error::kTempDirError);
-    return;
-  }
-
+void DestroyPartitionsOperation::StartImpl() {
   if (!base::CreateTemporaryFileInDir(temp_dir_.path(), &image_path_)) {
     Error(error::kTempFileError);
     return;
@@ -44,7 +37,7 @@ void DestroyPartitionsOperation::Start() {
     return;
   }
 
-  WriteStart();
+  Write(base::Bind(&DestroyPartitionsOperation::Finish, this));
 }
 
 }  // namespace image_writer