Allow kwargs to be passed to create_channel, update templates (via synth). (#8391)

Author: yoshi-automation

grafeas/.coveragerc

@@ -1,3 +1,4 @@
+# Generated by synthtool. DO NOT EDIT!
 [run]
 branch = True
 

grafeas/.flake8

@@ -1,3 +1,4 @@
+# Generated by synthtool. DO NOT EDIT!
 [flake8]
 ignore = E203, E266, E501, W503
 exclude =

grafeas/grafeas/grafeas_v1/gapic/transports/grafeas_grpc_transport.py

@@ -63,7 +63,7 @@ def __init__(self, address, scopes, channel=None, credentials=None):
         self._stubs = {"grafeas_stub": grafeas_pb2_grpc.GrafeasStub(channel)}
 
     @classmethod
-    def create_channel(cls, address, scopes, credentials=None):
+    def create_channel(cls, address, scopes, credentials=None, **kwargs):
         """Create and return a gRPC channel object.
 
         Args:
@@ -74,12 +74,14 @@ def create_channel(cls, address, scopes, credentials=None):
                 credentials identify this application to the service. If
                 none are specified, the client will attempt to ascertain
                 the credentials from the environment.
+            kwargs (dict): Keyword arguments, which are passed to the
+                channel creation.
 
         Returns:
             grpc.Channel: A gRPC channel object.
         """
         return google.api_core.grpc_helpers.create_channel(
-            address, credentials=credentials, scopes=scopes
+            address, credentials=credentials, scopes=scopes, **kwargs
         )
 
     @property