Correctly hash the input of MatchModuleWhitelistString() in pver4.

components/safe_browsing_db/v4_local_database_manager.cc

Index: components/safe_browsing_db/v4_local_database_manager.cc
diff --git a/components/safe_browsing_db/v4_local_database_manager.cc b/components/safe_browsing_db/v4_local_database_manager.cc
index 45748e4601eec7353fc74d4d88140c1aaccc994e..5bc0b30a92bf4c782d3d563c54def1daed23ee53 100644
--- a/components/safe_browsing_db/v4_local_database_manager.cc
+++ b/components/safe_browsing_db/v4_local_database_manager.cc
@@ -17,6 +17,7 @@
 #include "components/safe_browsing_db/v4_feature_list.h"
 #include "components/safe_browsing_db/v4_protocol_manager_util.h"
 #include "content/public/browser/browser_thread.h"
+#include "crypto/sha2.h"
 
 using content::BrowserThread;
 using base::TimeTicks;
@@ -304,16 +305,16 @@ bool V4LocalDatabaseManager::MatchMalwareIP(const std::string& ip_address) {
 }
 
 bool V4LocalDatabaseManager::MatchModuleWhitelistString(
-    const std::string& str) {
+    const std::string& module_filename) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-
   if (!enabled_ || !v4_database_) {
-    // To make sure we are conservative we return true.
+    // Fail open: Whitelist everything
     return true;
   }
 
+  FullHash hash = crypto::SHA256HashString(module_filename);
   return HandleHashSynchronously(
-      str, StoresToCheck({GetChromeFilenameClientIncidentId()}));
+      hash, StoresToCheck({GetChromeFilenameClientIncidentId()}));
 }
 
 ThreatSource V4LocalDatabaseManager::GetThreatSource() const {