Improve code coverage in CFX_PathData::GetZeroAreaPath().

Change the bug_1338 pixel test to have more variations to better
exercise all the code paths in CFX_PathData::GetZeroAreaPath().

Change-Id: I1b20e4e97e15fc1470dd992beddd5aca101b7ecb
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/57731
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

testing/resources/pixel/bug_1338.in

diff --git a/testing/resources/pixel/bug_1338.in b/testing/resources/pixel/bug_1338.in
index 70b9dfc..3700527 100644
--- a/testing/resources/pixel/bug_1338.in
+++ b/testing/resources/pixel/bug_1338.in
@@ -53,11 +53,21 @@
 Q
 q
 0.5 0 0 0.5 0 0 cm
+1 1 0 rg
+250 950 m
+50 925 l
+50 550 l
+50 950 l
+250 950 l
+f*
+Q
+q
+0.5 0 0 0.5 0 0 cm
 0 0 0 rg
 570 750 m
-500 850 l
-300 550 l
 450 775 l
+300 550 l
+500 850 l
 570 750 l
 f*
 Q

testing/resources/pixel/bug_1338_expected.pdf.0.png

diff --git a/testing/resources/pixel/bug_1338_expected.pdf.0.png b/testing/resources/pixel/bug_1338_expected.pdf.0.png
index 0151474..5048783 100644
--- a/testing/resources/pixel/bug_1338_expected.pdf.0.png
+++ b/testing/resources/pixel/bug_1338_expected.pdf.0.png
Binary files differ