Merge to XFA: Fix behaviour of app.alert() with a single object argument.

Original Review URL: https://codereview.chromium.org/1641693003 .
(cherry picked from commit 66519af52b61ca158044651d0507d47efb364f87)

TBR=thestig@chromium.org

Review URL: https://codereview.chromium.org/1639253008 .
diff --git a/samples/pdfium_test.cc b/samples/pdfium_test.cc
index b1bce51..8c0a249 100644
--- a/samples/pdfium_test.cc
+++ b/samples/pdfium_test.cc
@@ -195,10 +195,15 @@
 }
 #endif
 
-int ExampleAppAlert(IPDF_JSPLATFORM*, FPDF_WIDESTRING msg, FPDF_WIDESTRING,
-                    int, int) {
-  std::wstring platform_string = GetPlatformWString(msg);
-  printf("Alert: %ls\n", platform_string.c_str());
+int ExampleAppAlert(IPDF_JSPLATFORM*,
+                    FPDF_WIDESTRING msg,
+                    FPDF_WIDESTRING title,
+                    int nType,
+                    int nIcon) {
+  printf("%ls", GetPlatformWString(title).c_str());
+  if (nIcon || nType)
+    printf("[icon=%d,type=%d]", nIcon, nType);
+  printf(": %ls\n", GetPlatformWString(msg).c_str());
   return 0;
 }