Drop obsolete Skia suppressions

Drops obsolete Skia suppressions for pdfium:1859, pdfium:1863, and
pdfium:1968.

Bug: pdfium:1859, pdfium:1863, pdfium:1968
Change-Id: I604c31f5279c78de7ffb103d8a94d73d7b42bdf9
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/103911
Commit-Queue: K. Moon <kmoon@chromium.org>
Reviewed-by: Nigi <nigi@chromium.org>
diff --git a/DEPS b/DEPS
index 6ac1f42..a77fd99 100644
--- a/DEPS
+++ b/DEPS
@@ -140,7 +140,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling pdfium_tests
   # and whatever else without interference from each other.
-  'pdfium_tests_revision': '14a56b4fbdda976f1d1686f0c2dcfc1497e4547d',
+  'pdfium_tests_revision': '37329ea13227b005d3b68c324c14d1b664f19b76',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling resultdb
   # and whatever else without interference from each other.
diff --git a/testing/SUPPRESSIONS b/testing/SUPPRESSIONS
index 1bf5907..b2adb18 100644
--- a/testing/SUPPRESSIONS
+++ b/testing/SUPPRESSIONS
@@ -45,15 +45,9 @@
 2_halftone.pdf * * * skia
 
 3_4_textbox.pdf * * * *
-
 3_interpolate_image.pdf mac * * *
 3bigpreview.pdf mac * * *
-
 4_35.pdf mac * * *
-
-# TODO(pdfium:1859): Remove after associated bug is fixed
-4_36.pdf * * * skia
-
 4_39.pdf mac * * *
 5.1.pdf mac * * *
 5.2.pdf * * * *
@@ -260,13 +254,8 @@
 jetman_std_fixed.pdf mac * * *
 js_calculate.pdf * * * *
 list_box.pdf * * * *
-
 negative.pdf mac * * *
 new_certify1.pdf mac * * *
-
-# TODO(pdfium:1863): Remove after associated bug is fixed
-new_pdfsign1.pdf * * * skia
-
 new_signature1.pdf mac * * *
 new_signature2.pdf mac * * *
 new_stamp4.pdf mac * * *
@@ -394,9 +383,6 @@
 # TODO(pdfium:1963): Remove after associated bug is fixed
 bug_1963.in * * * skia
 
-# TODO(pdfium:1968): Remove after associated bug is fixed
-bug_1966.in * * * skia
-
 # TODO(pdfium:1973): Remove after associated bug is fixed
 bug_1973.in * * * agg,skia
 
diff --git a/testing/resources/pixel/bug_1966_expected_skia.pdf.0.png b/testing/resources/pixel/bug_1966_expected_skia.pdf.0.png
new file mode 100644
index 0000000..134ca64
--- /dev/null
+++ b/testing/resources/pixel/bug_1966_expected_skia.pdf.0.png
Binary files differ