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

chrome/browser/autocomplete/history_url_provider_unittest.cc

Index: chrome/browser/autocomplete/history_url_provider_unittest.cc
===================================================================
--- chrome/browser/autocomplete/history_url_provider_unittest.cc	(revision 105162)
+++ chrome/browser/autocomplete/history_url_provider_unittest.cc	(working copy)
@@ -376,7 +376,8 @@
   redirects_to_a.push_back(GURL(test_cases[2].url));
   redirects_to_a.push_back(GURL(test_cases[0].url));
   history_service_->AddPage(GURL(test_cases[0].url), NULL, 0, GURL(),
-      PageTransition::TYPED, redirects_to_a, history::SOURCE_BROWSED, true);
+      content::PAGE_TRANSITION_TYPED, redirects_to_a, history::SOURCE_BROWSED,
+      true);
 
   // Because all the results are part of a redirect chain with other results,
   // all but the first one (A) should be culled. We should get the default