Generate all extension schema namespaces as "api" and instead vary the generated bundle names.

extensions/common/cast/cast_cert_validator_nss.cc

Index: extensions/common/cast/cast_cert_validator_nss.cc
diff --git a/extensions/common/cast/cast_cert_validator_nss.cc b/extensions/common/cast/cast_cert_validator_nss.cc
index 425da28f30649f649085d63a2ddd0c3d6bc31a14..47b7648259798aef73ee9257cc65733ed892ed98 100644
--- a/extensions/common/cast/cast_cert_validator_nss.cc
+++ b/extensions/common/cast/cast_cert_validator_nss.cc
@@ -17,7 +17,7 @@
 #include "extensions/browser/api/cast_channel/cast_auth_ica.h"
 
 namespace extensions {
-namespace core_api {
+namespace api {
 namespace cast_crypto {
 
 namespace {
@@ -151,5 +151,5 @@ std::string VerificationResult::GetLogString() const {
 }
 
 }  // namespace cast_crypto
-}  // namespace core_api
+}  // namespace api
 }  // namespace extensions