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

content/common/webkitplatformsupport_impl.h

Index: content/common/webkitplatformsupport_impl.h
===================================================================
--- content/common/webkitplatformsupport_impl.h	(revision 163290)
+++ content/common/webkitplatformsupport_impl.h	(working copy)
@@ -10,10 +10,9 @@
 #include "ui/base/layout.h"
 #include "webkit/glue/webkitplatformsupport_impl.h"
 
+namespace content {
 class GpuChannelHostFactory;
 
-namespace content {
-
 // This is a specialization of WebKitPlatformSupportImpl that implements the
 // embedder functions in terms of ContentClient.
 class CONTENT_EXPORT WebKitPlatformSupportImpl