Merge r223423 - We should wrap the removal of information from the tr…

…acker database in a transaction in DatabaseTracker::deleteOrigin()

https://bugs.webkit.org/show_bug.cgi?id=178274
<rdar://problem/34576132>

Patch by Maureen Daum <mdaum@apple.com> on 2017-10-16
Reviewed by Tim Horton.

* Modules/webdatabase/DatabaseTracker.cpp:
(WebCore::DatabaseTracker::deleteOrigin):
Wrap the removal of information from the tracker database in a transaction so that
we don't end up in a case where only one of the tables contains information about
an origin.
If anything goes wrong when we're modifying the tracker database, rollback the transaction
before bailing.

Source/WebCore/ChangeLog

@@ -1,3 +1,19 @@
+2017-10-16  Maureen Daum  <mdaum@apple.com>
+
+        We should wrap the removal of information from the tracker database in a transaction in DatabaseTracker::deleteOrigin()
+        https://bugs.webkit.org/show_bug.cgi?id=178274
+        <rdar://problem/34576132>
+
+        Reviewed by Tim Horton.
+
+        * Modules/webdatabase/DatabaseTracker.cpp:
+        (WebCore::DatabaseTracker::deleteOrigin):
+        Wrap the removal of information from the tracker database in a transaction so that
+        we don't end up in a case where only one of the tables contains information about
+        an origin.
+        If anything goes wrong when we're modifying the tracker database, rollback the transaction
+        before bailing.
+
 2017-10-13  Brent Fulgham  <bfulgham@apple.com>
 
         Protect FrameView during style calculations

Source/WebCore/Modules/webdatabase/DatabaseTracker.cpp

@@ -42,6 +42,7 @@
 #include "SecurityOriginHash.h"
 #include "SQLiteFileSystem.h"
 #include "SQLiteStatement.h"
+#include "SQLiteTransaction.h"
 #include <wtf/MainThread.h>
 #include <wtf/NeverDestroyed.h>
 #include <wtf/StdLibExtras.h>
@@ -842,6 +843,9 @@ bool DatabaseTracker::deleteOrigin(const SecurityOriginData& origin, DeletionMod
         deleteOriginLockFor(origin);
         doneDeletingOrigin(origin);
 
+        SQLiteTransaction transaction(m_database);
+        transaction.begin();
+
         SQLiteStatement statement(m_database, "DELETE FROM Databases WHERE origin=?");
         if (statement.prepare() != SQLITE_OK) {
             LOG_ERROR("Unable to prepare deletion of databases from origin %s from tracker", origin.databaseIdentifier().utf8().data());
@@ -868,6 +872,8 @@ bool DatabaseTracker::deleteOrigin(const SecurityOriginData& origin, DeletionMod
             return false;
         }
 
+        transaction.commit();
+
         SQLiteFileSystem::deleteEmptyDatabaseDirectory(originPath(origin));
 
         bool isEmpty = true;