Cleanup: Move kAboutScheme constant into content namespace.

content/public/common/url_constants.h

Index: content/public/common/url_constants.h
diff --git a/content/public/common/url_constants.h b/content/public/common/url_constants.h
index 331914f80b63c8eec28ec66dbd8b1d1ea874415a..0d59cd14c16d683cc5d6381c0dc27e1a319c6dc2 100644
--- a/content/public/common/url_constants.h
+++ b/content/public/common/url_constants.h
@@ -9,17 +9,12 @@
 
 // Contains constants for known URLs and portions thereof.
 
-// TODO(jam): rename this to content.
-namespace chrome {
+namespace content {
 
 // Canonical schemes you can use as input to GURL.SchemeIs().
 // TODO(jam): some of these don't below in the content layer, but are accessed
 // from there.
 CONTENT_EXPORT extern const char kAboutScheme[];
-}  // namespace chrome
-
-namespace content {
-
 CONTENT_EXPORT extern const char kBlobScheme[];
 CONTENT_EXPORT extern const char kChromeDevToolsScheme[];
 CONTENT_EXPORT extern const char kChromeUIScheme[];  // Used for WebUIs.