Move a bunch of content\common code into the content namespace.

content/common/db_message_filter.cc

 // Copyright (c) 2011 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 "content/common/db_message_filter.h"
 
 #include "content/common/database_messages.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDatabase.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebString.h"
 
+namespace content {
+
 DBMessageFilter::DBMessageFilter() {
 }
 
 bool DBMessageFilter::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(DBMessageFilter, message)
     IPC_MESSAGE_HANDLER(DatabaseMsg_UpdateSize, OnDatabaseUpdateSize)
     IPC_MESSAGE_HANDLER(DatabaseMsg_UpdateSpaceAvailable,
                         OnDatabaseUpdateSpaceAvailable)
     IPC_MESSAGE_HANDLER(DatabaseMsg_ResetSpaceAvailable,
@@ skipping 23 matching lines @@
     const string16& origin_identifier) {
   WebKit::WebDatabase::resetSpaceAvailable(origin_identifier);
 }
 
 void DBMessageFilter::OnDatabaseCloseImmediately(
     const string16& origin_identifier,
     const string16& database_name) {
   WebKit::WebDatabase::closeDatabaseImmediately(
       origin_identifier, database_name);
 }
+
+}  // namespace content