Move PageTransition into content namespace. While I'm touching all these files, I've also updated...

chrome/browser/history/history_notifications.cc

 // Copyright (c) 2010 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 "chrome/browser/history/history_notifications.h"
 
 namespace history {
 
-URLVisitedDetails::URLVisitedDetails() : transition(PageTransition::LINK) {}
+URLVisitedDetails::URLVisitedDetails()
+    : transition(content::PAGE_TRANSITION_LINK) {}
 
 URLVisitedDetails::~URLVisitedDetails() {}
 
 URLsModifiedDetails::URLsModifiedDetails() {}
 
 URLsModifiedDetails::~URLsModifiedDetails() {}
 
 URLsDeletedDetails::URLsDeletedDetails() : all_history(false) {}
 
 URLsDeletedDetails::~URLsDeletedDetails() {}
 
 URLsStarredDetails::URLsStarredDetails(bool being_starred)
     : starred(being_starred) {
 }
 
 URLsStarredDetails::~URLsStarredDetails() {}
 
 FaviconChangeDetails::FaviconChangeDetails() {}
 
 FaviconChangeDetails::~FaviconChangeDetails() {}
 
 KeywordSearchTermDetails::KeywordSearchTermDetails() : keyword_id(0) {}
 
 KeywordSearchTermDetails::~KeywordSearchTermDetails() {}
 
 }  // namespace history