Remove axial gradients from XFA widgets.

Most of the CPU time when moving around XFA forms is spent rendering
these gradients.

Bug: chromium:592748
Change-Id: I08c68c60996755a2be25243dfd2143b6cbb13af9
Reviewed-on: https://pdfium-review.googlesource.com/28090
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
diff --git a/DEPS b/DEPS
index e08aa2a..a36329a 100644
--- a/DEPS
+++ b/DEPS
@@ -29,7 +29,7 @@
   'jinja2_revision': 'd34383206fa42d52faa10bb9931d6d538f3a57e0',
   'jpeg_turbo_revision': '7260e4d8b8e1e40b17f03fafdf1cd83296900f76',
   'markupsafe_revision': '8f45f5cfa0009d2a70589bcda0349b8cb2b72783',
-  'pdfium_tests_revision': 'adcc738d124799800ab2f3eb7cf0dfbd301cd759',
+  'pdfium_tests_revision': 'b86c0ec9ee2aa3ba5e113a0e88a5c3292eb0fe2f',
   'skia_revision': '40ca2087ef0752d78fd2e0995471102fe96fe9fe',
   'tools_memory_revision': '427f10475e1a8d72424c29d00bf689122b738e5d',
   'trace_event_revision': '0e9a47d74970bee1bbfc063c47215406f8918699',