Do not validity check safe-browsing store if not opened.

chrome/browser/safe_browsing/safe_browsing_store_file.cc

Index: chrome/browser/safe_browsing/safe_browsing_store_file.cc
diff --git a/chrome/browser/safe_browsing/safe_browsing_store_file.cc b/chrome/browser/safe_browsing/safe_browsing_store_file.cc
index 2159fa1ecf61a4d95adaf8129a58a5413c361bff..76a8958aad0b1f793849df313d44052d18da3b8a 100644
--- a/chrome/browser/safe_browsing/safe_browsing_store_file.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_store_file.cc
@@ -244,12 +244,13 @@ bool SafeBrowsingStoreFile::Delete() {
 }
 
 bool SafeBrowsingStoreFile::CheckValidity() {
-  if (empty_)
+  // The file was either empty or never opened.  The empty case is
+  // presumed not to be invalid.  The never-opened case can happen if
+  // BeginUpdate() fails for any databases, and should already have
+  // caused the corruption callback to fire.
+  if (!file_.get())
     return true;
 
-  // If the file was not empty, it should be open.
-  DCHECK(file_.get());
-
   if (!FileRewind(file_.get()))
     return OnCorruptDatabase();