Created new Task.h file to contain task classes.

Test: tested Reboot {target} + Flash {partition} on raven device
Bug: 194686221
Change-Id: I0d80230d682f80af12cca9705df0172651bf4461
diff --git a/fastboot/task.h b/fastboot/task.h
new file mode 100644
index 0000000..8b3fce9
--- /dev/null
+++ b/fastboot/task.h
@@ -0,0 +1,31 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#pragma once
+
+#include <sstream>
+#include <string>
+
+#include "fastboot.h"
+#include "fastboot_driver.h"
+#include "util.h"
+
+class Task {
+  public:
+    Task() = default;
+    virtual void Run() = 0;
+    virtual bool Parse(const std::string& text) = 0;
+    virtual ~Task() = default;
+};