Alter the ActivityLog db table schemas.

chrome/browser/extensions/activity_actions.cc

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <string>
+#include "base/logging.h"
+#include "base/stringprintf.h"
+#include "chrome/browser/extensions/api_actions.h"
+
+namespace extensions {
+
+// static
+bool Action::InitializeTableInternal(sql::Connection* db,
+                                     const char* table_name,
+                                     const char* basic_fields,
+                                     const char* content_fields[],
+                                     const int num_content_fields) {
+  if (!db->DoesTableExist(table_name)) {
+    std::string table_creator = base::StringPrintf(
+        "CREATE TABLE %s (%s", table_name, basic_fields);
+    for (int i = 0; i < num_content_fields; i++) {
+      table_creator += base::StringPrintf(", %s LONGVARCHAR",
+                                          content_fields[i]);
+    }
+    table_creator += ")";
+    if (!db->Execute(table_creator.c_str()))
+      return false;
+  } else {
+    // In case we ever want to add new fields, this initializes them to be
+    // empty strings.
+    for (int i = 0; i < num_content_fields; i++) {
+      if (!db->DoesColumnExist(table_name, content_fields[i])) {
+        std::string table_updater = base::StringPrintf(
+            "ALTER TABLE %s ADD COLUMN %s LONGVARCHAR; ",
+             table_name,
+             content_fields[i]);
+        if (!db->Execute(table_updater.c_str()))
+          return false;
+      }
+    }
+  }
+  return true;
+}
+
+}  // namespace extensions
+