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

extensions/browser/api/cast_channel/cast_channel_api.h

Index: extensions/browser/api/cast_channel/cast_channel_api.h
diff --git a/extensions/browser/api/cast_channel/cast_channel_api.h b/extensions/browser/api/cast_channel/cast_channel_api.h
index 2b1b6d8fc3299931b8eeed54a495804dcc949cb6..f3cf2793ad8fc37d0f7d04b3e307d8c020576118 100644
--- a/extensions/browser/api/cast_channel/cast_channel_api.h
+++ b/extensions/browser/api/cast_channel/cast_channel_api.h
@@ -31,13 +31,13 @@ namespace extensions {
 
 struct Event;
 
-namespace core_api {
+namespace api {
 namespace cast_channel {
 class Logger;
 }  // namespace cast_channel
-}  // namespace core_api
+}  // namespace api
 
-namespace cast_channel = core_api::cast_channel;
+namespace cast_channel = api::cast_channel;
 
 class CastChannelAPI : public BrowserContextKeyedAPI,
                        public base::SupportsWeakPtr<CastChannelAPI> {
@@ -167,7 +167,7 @@ class CastChannelOpenFunction : public CastChannelAsyncApiFunction {
    public:
     CastMessageHandler(const EventDispatchCallback& ui_dispatch_cb,
                        cast_channel::CastSocket* socket,
-                       scoped_refptr<core_api::cast_channel::Logger> logger);
+                       scoped_refptr<api::cast_channel::Logger> logger);
     ~CastMessageHandler() override;
 
     // CastTransport::Delegate implementation.
@@ -182,7 +182,7 @@ class CastChannelOpenFunction : public CastChannelAsyncApiFunction {
     EventDispatchCallback const ui_dispatch_cb_;
     cast_channel::CastSocket* const socket_;
     // Logger object for reporting error details.
-    scoped_refptr<core_api::cast_channel::Logger> logger_;
+    scoped_refptr<api::cast_channel::Logger> logger_;
 
     DISALLOW_COPY_AND_ASSIGN(CastMessageHandler);
   };