Add a whitelist for the new binary download protection.

chrome/browser/safe_browsing/safe_browsing_util.h

Index: chrome/browser/safe_browsing/safe_browsing_util.h
diff --git a/chrome/browser/safe_browsing/safe_browsing_util.h b/chrome/browser/safe_browsing/safe_browsing_util.h
index 2911f469133e5e2fc442e65671ddcb5a1dd9121b..577ffab53f811139dec30867cbbac2f2ea6c828d 100644
--- a/chrome/browser/safe_browsing/safe_browsing_util.h
+++ b/chrome/browser/safe_browsing/safe_browsing_util.h
@@ -266,6 +266,8 @@ extern const char kBinUrlList[];
 extern const char kBinHashList[];
 // SafeBrowsing client-side detection whitelist list name.
 extern const char kCsdWhiteList[];
+// SafeBrowsing download whitelist list name.
+extern const char kDownloadWhiteList[];
 
 enum ListType {
   INVALID = -1,
@@ -274,6 +276,10 @@ enum ListType {
   BINURL = 2,
   BINHASH = 3,
   CSDWHITELIST = 4,
+  // SafeBrowsing lists are stored in pairs.  Keep ListType 5
+  // available for a potential second list that we would store in the
+  // csd-whitelist store file.
+  DOWNLOADWHITELIST = 6,
 };
 
 // Maps a list name to ListType.