Add GDI + Skia expectation for transparent.pdf

With GDI + Skia, transparent.pdf renders the same as with Skia. Add a
new copy of transparent_expected_skia.pdf.0.png so the corpus test
matches this file.

Update the presubmit to allow for 2 new renderer variations in the file
names:

1) gdi_agg
2) gdi_skia

Bug: pdfium:2056,pdfium:2080
Change-Id: I03ee6568e508fe254941f2db197e7de884a0e489
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium_tests/+/112110
Reviewed-by: Nigi <nigi@chromium.org>

PRESUBMIT.py

diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 4681fd9..17315cd 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -28,12 +28,12 @@
   """Checks that .png files have the right file name format, which must be in
   the form:
 
-  NAME_expected(_(agg|gdi|skia))?(_(linux|mac|win))?.pdf.\d+.png
+  NAME_expected(_gdi)?(_(agg|skia))?(_(linux|mac|win))?.pdf.\d+.png
 
   This must be the same format as the one in PDFium's PRESUBMIT.py.
   """
   expected_pattern = input_api.re.compile(
-      r'.+_expected(_(agg|gdi|skia))?(_(linux|mac|win))?\.pdf\.\d+.png')
+      r'.+_expected(_gdi)?(_(agg|skia))?(_(linux|mac|win))?\.pdf\.\d+.png')
   results = []
   for f in input_api.AffectedFiles(include_deletes=False):
     if not f.LocalPath().endswith('.png'):

fx/image/3_image_imagemask_expected_gdi_skia.pdf.0.png

diff --git a/fx/image/3_image_imagemask_expected_gdi_skia.pdf.0.png b/fx/image/3_image_imagemask_expected_gdi_skia.pdf.0.png
new file mode 100644
index 0000000..3f0bc27
--- /dev/null
+++ b/fx/image/3_image_imagemask_expected_gdi_skia.pdf.0.png
Binary files differ

fx/path/11_expected_gdi_skia.pdf.0.png

diff --git a/fx/path/11_expected_gdi_skia.pdf.0.png b/fx/path/11_expected_gdi_skia.pdf.0.png
new file mode 100644
index 0000000..00636b9
--- /dev/null
+++ b/fx/path/11_expected_gdi_skia.pdf.0.png
Binary files differ

fx/path/transparent_expected_gdi_agg.pdf.0.png

diff --git a/fx/path/transparent_expected_gdi_agg.pdf.0.png b/fx/path/transparent_expected_gdi_agg.pdf.0.png
new file mode 100644
index 0000000..957f798
--- /dev/null
+++ b/fx/path/transparent_expected_gdi_agg.pdf.0.png
Binary files differ

fx/path/transparent_expected_gdi_skia.pdf.0.png

diff --git a/fx/path/transparent_expected_gdi_skia.pdf.0.png b/fx/path/transparent_expected_gdi_skia.pdf.0.png
new file mode 100644
index 0000000..57b9d9b
--- /dev/null
+++ b/fx/path/transparent_expected_gdi_skia.pdf.0.png
Binary files differ