Handle overlapping links and widgets.

core/src/fpdfdoc/doc_form.cpp

Index: core/src/fpdfdoc/doc_form.cpp
diff --git a/core/src/fpdfdoc/doc_form.cpp b/core/src/fpdfdoc/doc_form.cpp
index d695cb98bab8aa6087d163ca5512c24c8fe58a18..1c1966f6e471ce7619f58b9400cff0c2945b35b2 100644
--- a/core/src/fpdfdoc/doc_form.cpp
+++ b/core/src/fpdfdoc/doc_form.cpp
@@ -903,6 +903,14 @@ CPDF_FormControl* CPDF_InterForm::GetControlAtPoint(CPDF_Page* pPage, FX_FLOAT p
         }
         CPDF_FormControl* pControl;
         if (!m_ControlMap.Lookup(pAnnot, (FX_LPVOID&)pControl)) {
+            // If there is a link that overlaps the widget, return NULL.
+            if (pAnnot->GetString("Subtype") == "Link") {
+                CPDF_Link link(pAnnot);
+                CPDF_Rect link_rect = link.GetRect();
+                if (link_rect.Contains(pdf_x, pdf_y)) {
+                    return NULL;
+                }
+            }
             continue;
         }
         CFX_FloatRect rect = pControl->GetRect();