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.cc

Index: content/common/fileapi/webfilesystem_callback_dispatcher.cc
===================================================================
--- content/common/fileapi/webfilesystem_callback_dispatcher.cc	(revision 163290)
+++ content/common/fileapi/webfilesystem_callback_dispatcher.cc	(working copy)
@@ -24,6 +24,8 @@
 using WebKit::WebString;
 using WebKit::WebVector;
 
+namespace content {
+
 WebFileSystemCallbackDispatcher::WebFileSystemCallbackDispatcher(
     WebFileSystemCallbacks* callbacks)
     : callbacks_(callbacks) {
@@ -67,3 +69,5 @@
 void WebFileSystemCallbackDispatcher::DidWrite(int64 bytes, bool complete) {
   NOTREACHED();
 }
+
+}  // namespace content