Get code coverage for CPDFSDK_Widget::Synchronize()

These tests require a mixed XFA form (i.e. no <config> XFA section,
just a <template> section, say) with a PDF widget not overlapped by
an XFA widget, and an XFA widget linked by the same name to the PDF
widget.

Send a click then type into the PDF widget to force it to sync
with the XFA one.

Change-Id: I71c5b346770b7da3045322b6af5765703f188556
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/104512
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
diff --git a/testing/resources/javascript/xfa_specific/mixed_widgets.evt b/testing/resources/javascript/xfa_specific/mixed_widgets.evt
new file mode 100644
index 0000000..f4ee07d
--- /dev/null
+++ b/testing/resources/javascript/xfa_specific/mixed_widgets.evt
@@ -0,0 +1,5 @@
+mousemove,302,302
+mousedown,left,302,302
+mouseup,left,302,302
+charcode,65
+charcode,66
diff --git a/testing/resources/javascript/xfa_specific/mixed_widgets.in b/testing/resources/javascript/xfa_specific/mixed_widgets.in
new file mode 100644
index 0000000..2974112
--- /dev/null
+++ b/testing/resources/javascript/xfa_specific/mixed_widgets.in
@@ -0,0 +1,48 @@
+{{header}}
+{{object 1 0}} <<
+  /Type /Catalog
+  /Pages 2 0 R
+  /NeedsRendering true
+  /AcroForm <<
+    /Fields [6 0 R]
+    /XFA 5 0 R
+  >>
+>>
+endobj
+{{object 2 0}} <<
+  /Type /Pages
+  /Count 1
+  /Kids [4 0 R]
+>>
+endobj
+{{object 4 0}} <<
+  /Type /Page
+  /Parent 2 0 R
+  /MediaBox [0 0 512 512]
+  /Annots [6 0 R]
+>>
+endobj
+{{object 5 0}} <<
+  {{streamlen}}
+>>
+stream
+<xdp xmlns="http://ns.adobe.com/xdp/">
+  <template>
+    <subform x="0pt" y="0pt" w="198pt" h="198pt">
+      <field name="MyBox"/>
+    </subform>
+  </template>
+</xdp>
+endstream
+endobj
+{{object 6 0}} <<
+  /Type /Annot
+  /Subtype /Widget
+  /FT /Tx
+  /Rect [200 200 512 512]
+  /T (MyBox)
+>>
+{{xref}}
+{{trailer}}
+{{startxref}}
+%%EOF