browser-thread related exports

R=jam@chromium.org
BUG=
TEST=

Review URL: http://codereview.chromium.org/8341129

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@107998 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/browser_thread_impl.h

@@ -6,11 +6,12 @@
 #define CONTENT_BROWSER_BROWSER_THREAD_IMPL_H_
 #pragma once
 
+#include "content/common/content_export.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace content {
 
-class BrowserThreadImpl : public BrowserThread {
+class CONTENT_EXPORT BrowserThreadImpl : public BrowserThread {
  public:
   explicit BrowserThreadImpl(BrowserThread::ID identifier);
   BrowserThreadImpl(BrowserThread::ID identifier, MessageLoop* message_loop);

content/public/browser/browser_thread.h

@@ -242,7 +242,7 @@ class CONTENT_EXPORT BrowserThread : public base::Thread {
 
 // Temporary escape hatch for chrome/ to construct BrowserThread,
 // until we make content/ construct its own threads.
-class DeprecatedBrowserThread : public BrowserThread {
+class CONTENT_EXPORT DeprecatedBrowserThread : public BrowserThread {
  public:
   explicit DeprecatedBrowserThread(BrowserThread::ID identifier);
   DeprecatedBrowserThread(BrowserThread::ID identifier,