Add noexcept to move constructors and assignment operators.

Bug: 116614593
Test: build with WITH_TIDY=1
Change-Id: I5a7461386946ca623ab509609092aa0ac8418b80
diff --git a/libziparchive/zip_writer.cc b/libziparchive/zip_writer.cc
index 6ad3366..ed1d135 100644
--- a/libziparchive/zip_writer.cc
+++ b/libziparchive/zip_writer.cc
@@ -97,7 +97,7 @@
   }
 }
 
-ZipWriter::ZipWriter(ZipWriter&& writer)
+ZipWriter::ZipWriter(ZipWriter&& writer) noexcept
     : file_(writer.file_),
       seekable_(writer.seekable_),
       current_offset_(writer.current_offset_),
@@ -109,7 +109,7 @@
   writer.state_ = State::kError;
 }
 
-ZipWriter& ZipWriter::operator=(ZipWriter&& writer) {
+ZipWriter& ZipWriter::operator=(ZipWriter&& writer) noexcept {
   file_ = writer.file_;
   seekable_ = writer.seekable_;
   current_offset_ = writer.current_offset_;