Change filename to channelz

gRPC-Core.podspec

diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index 89cc95f..f3be712 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -357,7 +357,7 @@
                       'src/core/lib/channel/channel_stack.h',
                       'src/core/lib/channel/channel_stack_builder.h',
                       'src/core/lib/channel/channel_trace.h',
-                      'src/core/lib/channel/channel_trace_registry.h',
+                      'src/core/lib/channel/channelz_registry.h',
                       'src/core/lib/channel/connected_channel.h',
                       'src/core/lib/channel/context.h',
                       'src/core/lib/channel/handshaker.h',
@@ -507,7 +507,7 @@
                       'src/core/lib/channel/channel_stack.cc',
                       'src/core/lib/channel/channel_stack_builder.cc',
                       'src/core/lib/channel/channel_trace.cc',
-                      'src/core/lib/channel/channel_trace_registry.cc',
+                      'src/core/lib/channel/channelz_registry.cc',
                       'src/core/lib/channel/connected_channel.cc',
                       'src/core/lib/channel/handshaker.cc',
                       'src/core/lib/channel/handshaker_factory.cc',
@@ -935,7 +935,7 @@
                               'src/core/lib/channel/channel_stack.h',
                               'src/core/lib/channel/channel_stack_builder.h',
                               'src/core/lib/channel/channel_trace.h',
-                              'src/core/lib/channel/channel_trace_registry.h',
+                              'src/core/lib/channel/channelz_registry.h',
                               'src/core/lib/channel/connected_channel.h',
                               'src/core/lib/channel/context.h',
                               'src/core/lib/channel/handshaker.h',