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

content/renderer/mhtml_generator.cc

Index: content/renderer/mhtml_generator.cc
===================================================================
--- content/renderer/mhtml_generator.cc	(revision 163045)
+++ content/renderer/mhtml_generator.cc	(working copy)
@@ -10,8 +10,10 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebCString.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPageSerializer.h"
 
+namespace content {
+
 MHTMLGenerator::MHTMLGenerator(RenderViewImpl* render_view)
-    : content::RenderViewObserver(render_view),
+    : RenderViewObserver(render_view),
       file_(base::kInvalidPlatformFileValue) {
 }
 
@@ -63,3 +65,5 @@
   }
   return total_bytes_written;
 }
+
+}  // namespace content