Update {virtual,override} to follow C++11 style in net.

net/base/elements_upload_data_stream_unittest.cc

Index: net/base/elements_upload_data_stream_unittest.cc
diff --git a/net/base/elements_upload_data_stream_unittest.cc b/net/base/elements_upload_data_stream_unittest.cc
index e2a431cd79a24d770576b9065fbeaa04b56ee050..78229d2f76d366132472cb65dddae9604c0b0fa2 100644
--- a/net/base/elements_upload_data_stream_unittest.cc
+++ b/net/base/elements_upload_data_stream_unittest.cc
@@ -64,13 +64,13 @@ class MockUploadElementReader : public UploadElementReader {
         init_result_(OK),
         read_result_(OK) {}
 
-  virtual ~MockUploadElementReader() {}
+  ~MockUploadElementReader() override {}
 
   // UploadElementReader overrides.
   MOCK_METHOD1(Init, int(const CompletionCallback& callback));
-  virtual uint64 GetContentLength() const override { return content_length_; }
-  virtual uint64 BytesRemaining() const override { return bytes_remaining_; }
-  virtual bool IsInMemory() const override { return is_in_memory_; }
+  uint64 GetContentLength() const override { return content_length_; }
+  uint64 BytesRemaining() const override { return bytes_remaining_; }
+  bool IsInMemory() const override { return is_in_memory_; }
   MOCK_METHOD3(Read, int(IOBuffer* buf,
                          int buf_length,
                          const CompletionCallback& callback));