Rename extension_manifest_keys namespace to extensions::manifest_keys.

chrome/browser/extensions/api/spellcheck/spellcheck_api.cc

Index: chrome/browser/extensions/api/spellcheck/spellcheck_api.cc
diff --git a/chrome/browser/extensions/api/spellcheck/spellcheck_api.cc b/chrome/browser/extensions/api/spellcheck/spellcheck_api.cc
index 8c43e53f7b42cfa85080e7689385c1bd2672fb50..2c779dcd750ca4c6e853cc2e721c0719730d3703 100644
--- a/chrome/browser/extensions/api/spellcheck/spellcheck_api.cc
+++ b/chrome/browser/extensions/api/spellcheck/spellcheck_api.cc
@@ -15,7 +15,6 @@
 
 namespace extensions {
 
-namespace keys = extension_manifest_keys;
 namespace errors = extension_manifest_errors;
 
 namespace {
@@ -24,7 +23,7 @@ SpellcheckDictionaryInfo* GetSpellcheckDictionaryInfo(
     const Extension* extension) {
   SpellcheckDictionaryInfo *spellcheck_info =
       static_cast<SpellcheckDictionaryInfo*>(
-          extension->GetManifestData(keys::kSpellcheck));
+          extension->GetManifestData(manifest_keys::kSpellcheck));
   return spellcheck_info;
 }