Fixed optional content not rendered when OCGs array is empty.chromium/3138

At least one nonnull entry needs to be in OCGs for it to be considered
present. See "OCGs" in table 4.49 in the PDF 1.7 spec.

Bug: pdfium:491.
Change-Id: I7eae65ba1fabff9cf1d5cea50d059a04814a3fec
Reviewed-on: https://pdfium-review.googlesource.com/6751
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

6 files changed, 224 insertions, 0 deletions

diff --git a/testing/resources/pixel/bug_491_invisible.in b/testing/resources/pixel/bug_491_invisible.in
new file mode 100644
index 0000000000..75b7e58c5f
--- /dev/null
+++ b/testing/resources/pixel/bug_491_invisible.in
@@ -0,0 +1,75 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+  /OCProperties <<
+    /OCGs [
+      8 0 R
+    ]
+    /D <<
+      /BaseState /OFF
+    >>
+  >>
+>>
+{{object 2 0}} <<
+  /Type /Pages
+  /MediaBox [ 0 0 200 200 ]
+  /Count 1
+  /Kids [ 3 0 R ]
+>>
+endobj
+{{object 3 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /Resources <<
+    /Font <<
+      /F1 4 0 R
+      /F2 5 0 R
+    >>
+    /Properties <<
+      /OC0 7 0 R
+    >>
+  >>
+  /Contents 6 0 R
+>>
+endobj
+{{object 4 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Times-Roman
+>>
+endobj
+{{object 5 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Helvetica
+>>
+endobj
+{{object 6 0}} <<
+>>
+stream
+16 96 32 32 re B
+/OC /OC0 BDC
+64 96 32 32 re B
+EMC
+endstream
+endobj
+{{object 7 0}} <<
+  /OCGs [
+    8 0 R
+  ]
+  /Type /OCMD
+>>
+endobj
+{{object 8 0}} <<
+  /Type /OCG
+  /Name (Show Text)
+>>
+endobj
+{{xref}}
+trailer <<
+  /Size 9
+  /Root 1 0 R
+>>
+{{startxref}}
+%%EOF
diff --git a/testing/resources/pixel/bug_491_invisible_expected.pdf.0.png b/testing/resources/pixel/bug_491_invisible_expected.pdf.0.png
new file mode 100644
index 0000000000..067ca22f15
--- /dev/null
+++ b/testing/resources/pixel/bug_491_invisible_expected.pdf.0.png
diff --git a/testing/resources/pixel/bug_491_unspecified.in b/testing/resources/pixel/bug_491_unspecified.in
new file mode 100644
index 0000000000..b1e7312935
--- /dev/null
+++ b/testing/resources/pixel/bug_491_unspecified.in
@@ -0,0 +1,74 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+  /OCProperties <<
+    /OCGs [
+      8 0 R
+    ]
+    /D <<
+      /BaseState /OFF
+    >>
+  >>
+>>
+{{object 2 0}} <<
+  /Type /Pages
+  /MediaBox [ 0 0 200 200 ]
+  /Count 1
+  /Kids [ 3 0 R ]
+>>
+endobj
+{{object 3 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /Resources <<
+    /Font <<
+      /F1 4 0 R
+      /F2 5 0 R
+    >>
+    /Properties <<
+      /OC0 7 0 R
+    >>
+  >>
+  /Contents 6 0 R
+>>
+endobj
+{{object 4 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Times-Roman
+>>
+endobj
+{{object 5 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Helvetica
+>>
+endobj
+{{object 6 0}} <<
+>>
+stream
+16 96 32 32 re B
+/OC /OC0 BDC
+64 96 32 32 re B
+EMC
+endstream
+endobj
+{{object 7 0}} <<
+  /OCGs [
+  ]
+  /Type /OCMD
+>>
+endobj
+{{object 8 0}} <<
+  /Type /OCG
+  /Name (Show Text)
+>>
+endobj
+{{xref}}
+trailer <<
+  /Size 9
+  /Root 1 0 R
+>>
+{{startxref}}
+%%EOF
diff --git a/testing/resources/pixel/bug_491_unspecified_expected.pdf.0.png b/testing/resources/pixel/bug_491_unspecified_expected.pdf.0.png
new file mode 100644
index 0000000000..fa1b37c882
--- /dev/null
+++ b/testing/resources/pixel/bug_491_unspecified_expected.pdf.0.png
diff --git a/testing/resources/pixel/bug_491_visible.in b/testing/resources/pixel/bug_491_visible.in
new file mode 100644
index 0000000000..8e21b6c09b
--- /dev/null
+++ b/testing/resources/pixel/bug_491_visible.in
@@ -0,0 +1,75 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+  /OCProperties <<
+    /OCGs [
+      8 0 R
+    ]
+    /D <<
+      /BaseState /ON
+    >>
+  >>
+>>
+{{object 2 0}} <<
+  /Type /Pages
+  /MediaBox [ 0 0 200 200 ]
+  /Count 1
+  /Kids [ 3 0 R ]
+>>
+endobj
+{{object 3 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /Resources <<
+    /Font <<
+      /F1 4 0 R
+      /F2 5 0 R
+    >>
+    /Properties <<
+      /OC0 7 0 R
+    >>
+  >>
+  /Contents 6 0 R
+>>
+endobj
+{{object 4 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Times-Roman
+>>
+endobj
+{{object 5 0}} <<
+  /Type /Font
+  /Subtype /Type1
+  /BaseFont /Helvetica
+>>
+endobj
+{{object 6 0}} <<
+>>
+stream
+16 96 32 32 re B
+/OC /OC0 BDC
+64 96 32 32 re B
+EMC
+endstream
+endobj
+{{object 7 0}} <<
+  /OCGs [
+    8 0 R
+  ]
+  /Type /OCMD
+>>
+endobj
+{{object 8 0}} <<
+  /Type /OCG
+  /Name (Show Text)
+>>
+endobj
+{{xref}}
+trailer <<
+  /Size 9
+  /Root 1 0 R
+>>
+{{startxref}}
+%%EOF
diff --git a/testing/resources/pixel/bug_491_visible_expected.pdf.0.png b/testing/resources/pixel/bug_491_visible_expected.pdf.0.png
new file mode 100644
index 0000000000..fa1b37c882
--- /dev/null
+++ b/testing/resources/pixel/bug_491_visible_expected.pdf.0.png