Adding a SQL implementation of the backing store for previews opt outs

chrome/common/chrome_constants.cc

Index: chrome/common/chrome_constants.cc
diff --git a/chrome/common/chrome_constants.cc b/chrome/common/chrome_constants.cc
index 0a96fa23db6edb6f24d10280467835d14871952e..c8a4ef1cfed6f436f2bf6927193e39432c4491c3 100644
--- a/chrome/common/chrome_constants.cc
+++ b/chrome/common/chrome_constants.cc
@@ -149,20 +149,22 @@ const base::FilePath::CharType kLocalStorePoolName[] = FPL("LocalStorePool");
 const base::FilePath::CharType kMediaCacheDirname[] = FPL("Media Cache");
 const base::FilePath::CharType kNetworkPersistentStateFilename[] =
     FPL("Network Persistent State");
 const base::FilePath::CharType kOfflinePageArchivesDirname[] =
     FPL("Offline Pages/archives");
 const base::FilePath::CharType kOfflinePageMetadataDirname[] =
     FPL("Offline Pages/metadata");
 const base::FilePath::CharType kOfflinePageRequestQueueDirname[] =
     FPL("Offline Pages/request_queue");
 const base::FilePath::CharType kPreferencesFilename[] = FPL("Preferences");
+const base::FilePath::CharType kPreviewsOptOutDBFilename[] =
+    FPL("Previews/opt_out.db");

[Scott Hess - ex-Googler, 2016/10/08 00:04:22]

Would this directory need to exist otherwise?

I think "Offline Pages" has various other things in there.  Most dbs like
History and Top Sites just live in the profile rather than adding a new
directory layer.  I think that's preferred, as long as you're naming in a way
which makes it easy to find you (like "Previews Opt Out").

[Yes, many databases have spaces in their name, yes they use Leading Caps, and
yes they don't tend to have a suffix.  Predates my input.  Just don't name them
.sqlite, the SQLite team hates having people bug them for other people's
software.]

[RyanSturm, 2016/10/10 18:50:35]

Done.

 const base::FilePath::CharType kProtectedPreferencesFilenameDeprecated[] =
     FPL("Protected Preferences");
 const base::FilePath::CharType kReadmeFilename[] = FPL("README");
 const base::FilePath::CharType kSafeBrowsingBaseFilename[] =
     FPL("Safe Browsing");
 const base::FilePath::CharType kSecurePreferencesFilename[] =
     FPL("Secure Preferences");
 const base::FilePath::CharType kServiceStateFileName[] = FPL("Service State");
 const base::FilePath::CharType kSingletonCookieFilename[] =
     FPL("SingletonCookie");