Add test expectations for standard_symbols.pdf.

This pixel test is missing test expectation files.

Change-Id: I4b49ff669910d19678cdc99777f7e1fba379949f
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/70918
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.0.png

diff --git a/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.0.png b/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.0.png
new file mode 100644
index 0000000..62f3156
--- /dev/null
+++ b/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.0.png
Binary files differ

testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.1.png

diff --git a/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.1.png b/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.1.png
new file mode 100644
index 0000000..e262e83
--- /dev/null
+++ b/testing/resources/pixel/xfa_specific/standard_symbols_expected.pdf.1.png
Binary files differ