Add in count value for form types

BUG=chromium:775519,chromium:768986

Adding metric form types

Change-Id: Ic99a5ac988998986f06cb79d08458afeda49a5d1
Reviewed-on: https://pdfium-review.googlesource.com/16392
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
diff --git a/public/fpdf_formfill.h b/public/fpdf_formfill.h
index 0204c84..5bc3cf3 100644
--- a/public/fpdf_formfill.h
+++ b/public/fpdf_formfill.h
@@ -12,11 +12,14 @@
 
 typedef void* FPDF_FORMHANDLE;
 
+// These values are return values for a public API, so should not be changed
+// other than the count when adding new values.
 #define FORMTYPE_NONE 0       // Document contains no forms
 #define FORMTYPE_ACRO_FORM 1  // Forms are specified using AcroForm spec
 #define FORMTYPE_XFA_FULL 2   // Forms are specified using the entire XFA spec
 #define FORMTYPE_XFA_FOREGROUND \
   3  // Forms are specified using the XFAF subset of XFA spec
+#define FORMTYPE_COUNT 4  // The number of form types
 
 // Exported Functions
 #ifdef __cplusplus
diff --git a/xfa/fxfa/fxfa.h b/xfa/fxfa/fxfa.h
index ee74fc1..bb6864a 100644
--- a/xfa/fxfa/fxfa.h
+++ b/xfa/fxfa/fxfa.h
@@ -45,7 +45,7 @@
   kNone = 0,
   kAcroForm = 1,
   kXFAFull = 2,
-  kXFAForeground = 3
+  kXFAForeground = 3,
 };
 
 #define XFA_PARSESTATUS_StatusErr -3