LibCore: Add support for range-based for loops on LineIterators

Author: https://github.com/ccapitalK
Commit: 2c43eaa50c
Pull-request: https://github.com/SerenityOS/serenity/pull/11173
Reviewed-by: https://github.com/alimpfard
Reviewed-by: https://github.com/bgianfo

Userland/Libraries/LibCore/IODevice.cpp

@@ -319,4 +319,8 @@ LineIterator& LineIterator::operator++()
     m_buffer = m_device->read_line();
     return *this;
 }
+
+LineIterator LineRange::begin() { return m_device.line_begin(); }
+LineIterator LineRange::end() { return m_device.line_end(); }
+
 }