Merge to XFA: Fix segv above CPDFSDK_Document::GetPageView()

Original Review URL: https://codereview.chromium.org/1261923003 .
(cherry picked from commit d1a588c6ce03425773594381a0966434016813b1)

BUG=514690
R=thestig@chromium.org
TBR=thestig@chromium.org

Review URL: https://codereview.chromium.org/1254383007 .

2 files changed, 15 insertions, 0 deletions

diff --git a/fpdfsdk/src/fpdfformfill.cpp b/fpdfsdk/src/fpdfformfill.cpp
index 20beedd84a..aa1c04a5c4 100644
--- a/fpdfsdk/src/fpdfformfill.cpp
+++ b/fpdfsdk/src/fpdfformfill.cpp
@@ -31,6 +31,9 @@ CPDFSDK_InterForm* FormHandleToInterForm(FPDF_FORMHANDLE hHandle)
 
 CPDFSDK_PageView* FormHandleToPageView(FPDF_FORMHANDLE hHandle, FPDF_PAGE page)
 {
+    if (!page)
+        return nullptr;
+
     CPDFSDK_Document* pSDKDoc = FormHandleToSDKDoc(hHandle);
     return pSDKDoc ? pSDKDoc->GetPageView((CPDFXFA_Page*)page, TRUE) : nullptr;
 }
diff --git a/fpdfsdk/src/fpdfformfill_embeddertest.cpp b/fpdfsdk/src/fpdfformfill_embeddertest.cpp
index 615ada99f9..1c38770edb 100644
--- a/fpdfsdk/src/fpdfformfill_embeddertest.cpp
+++ b/fpdfsdk/src/fpdfformfill_embeddertest.cpp
@@ -41,3 +41,15 @@ TEST_F(FPDFFormFillEmbeddertest, BUG_487928) {
   delegate.AdvanceTime(5000);
   UnloadPage(page);
 }
+
+TEST_F(FPDFFormFillEmbeddertest, BUG_514690) {
+  EXPECT_TRUE(OpenDocument("testing/resources/hello_world.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  EXPECT_NE(nullptr, page);
+
+  // Test that FORM_OnMouseMove() etc. permit null HANDLES and PAGES.
+  FORM_OnMouseMove(nullptr, page, 0, 10.0, 10.0);
+  FORM_OnMouseMove(form_handle(), nullptr, 0, 10.0, 10.0);
+
+  UnloadPage(page);
+}