Split BrowserThread into public API and private implementation, step 1.

Only content/ now has the ability to create BrowserThread objects,
with the exception that tests can create the
content::TestBrowserThread subclass, and (temporarily) code in chrome/
can create the DeprecatedBrowserThread subclass.

A follow-up change will make content/ take care of its own thread
creation, remove DeprecatedBrowserThread, and move all state and
non-trivial constructors from BrowserThread down to BrowserThreadImpl.

Also moved BrowserProcessSubThread into content/ namespace.  As part
of follow-up cleanup, chrome/ will stop using this class.

BUG=98716
TEST=existing

Review URL: http://codereview.chromium.org/8392042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@107718 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/browsing_data_appcache_helper.cc b/chrome/browser/browsing_data_appcache_helper.cc
index b344b1c..f88e21e 100644
--- a/chrome/browser/browsing_data_appcache_helper.cc
+++ b/chrome/browser/browsing_data_appcache_helper.cc
@@ -8,7 +8,7 @@
 #include "chrome/browser/net/chrome_url_request_context.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/url_constants.h"
-#include "content/browser/browser_thread.h"
+#include "content/public/browser/browser_thread.h"
 #include "webkit/appcache/appcache_database.h"
 #include "webkit/appcache/appcache_storage.h"