Move a bunch of code in content\renderer to the content namespace.

content/renderer/load_progress_tracker.h

Index: content/renderer/load_progress_tracker.h
===================================================================
--- content/renderer/load_progress_tracker.h	(revision 163007)
+++ content/renderer/load_progress_tracker.h	(working copy)
@@ -9,12 +9,13 @@
 #include "base/memory/weak_ptr.h"
 #include "base/time.h"
 
-class RenderViewImpl;
-
 namespace WebKit {
 class WebFrame;
 }
 
+namespace content {
+class RenderViewImpl;
+
 class LoadProgressTracker {
  public:
   explicit LoadProgressTracker(RenderViewImpl* render_view);
@@ -42,4 +43,6 @@
   DISALLOW_COPY_AND_ASSIGN(LoadProgressTracker);
 };
 
+}  // namespace content
+
 #endif  // CONTENT_RENDERER_LOAD_PROGRESS_TRACKER_H_