Move the remaning files in content\common to the content namespace.

content/common/npobject_proxy.h

Index: content/common/npobject_proxy.h
===================================================================
--- content/common/npobject_proxy.h	(revision 163632)
+++ content/common/npobject_proxy.h	(working copy)
@@ -16,9 +16,11 @@
 #include "third_party/npapi/bindings/npruntime.h"
 #include "ui/gfx/native_widget_types.h"
 
-class NPChannelBase;
 struct NPObject;
 
+namespace content {
+class NPChannelBase;
+
 // When running a plugin in a different process from the renderer, we need to
 // proxy calls to NPObjects across process boundaries.  This happens both ways,
 // as a plugin can get an NPObject for the window, and a page can get an
@@ -120,4 +122,6 @@
   GURL page_url_;
 };
 
+}  // namespace content
+
 #endif  // CONTENT_COMMON_NPOBJECT_PROXY_H_