Move a bunch of code in content\common (as well as a few left in renderer) to the content namespace.

content/common/fileapi/webfilesystem_callback_dispatcher.h

Index: content/common/fileapi/webfilesystem_callback_dispatcher.h
===================================================================
--- content/common/fileapi/webfilesystem_callback_dispatcher.h	(revision 163290)
+++ content/common/fileapi/webfilesystem_callback_dispatcher.h	(working copy)
@@ -15,6 +15,8 @@
 class WebFileSystemCallbacks;
 }
 
+namespace content {
+
 class WebFileSystemCallbackDispatcher
     : public fileapi::FileSystemCallbackDispatcher {
  public:
@@ -38,4 +40,6 @@
   WebKit::WebFileSystemCallbacks* callbacks_;
 };
 
+}  // namespace content
+
 #endif  // CONTENT_COMMON_FILEAPI_WEBFILESYSTEM_CALLBACK_DISPATCHER_H_