Fix various typos in .cc and .md and .py files

Author: xichengliudui

src/cpp/codegen/codegen_init.cc

@@ -20,7 +20,7 @@
 #include <grpcpp/impl/codegen/grpc_library.h>
 
 /// Null-initializes the global gRPC variables for the codegen library. These
-/// stay null in the absence of of grpc++ library. In this case, no gRPC
+/// stay null in the absence of grpc++ library. In this case, no gRPC
 /// features such as the ability to perform calls will be available. Trying to
 /// perform them would result in a segmentation fault when trying to deference
 /// the following nulled globals. These should be associated with actual

src/ruby/pb/README.md

@@ -7,7 +7,7 @@ code to them.
 PREREQUISITES
 -------------
 
-The code is is generated using the protoc (> 3.0.0.alpha.1) and the
+The code is generated using the protoc (> 3.0.0.alpha.1) and the
 grpc_ruby_plugin.  These must be installed to regenerate the IDL defined
 classes, but that's not necessary just to use them.
 

test/core/end2end/fixtures/http_proxy_fixture.cc

@@ -78,7 +78,7 @@ struct grpc_end2end_http_proxy {
 //
 
 // proxy_connection structure is only accessed in the closures which are all
-// scheduled under the same combiner lock. So there is is no need for a mutex to
+// scheduled under the same combiner lock. So there is no need for a mutex to
 // protect this structure.
 typedef struct proxy_connection {
   grpc_end2end_http_proxy* proxy;

test/cpp/util/proto_reflection_descriptor_database.h

@@ -44,7 +44,7 @@ class ProtoReflectionDescriptorDatabase : public protobuf::DescriptorDatabase {
 
   // The following four methods implement DescriptorDatabase interfaces.
   //
-  // Find a file by file name.  Fills in in *output and returns true if found.
+  // Find a file by file name.  Fills in *output and returns true if found.
   // Otherwise, returns false, leaving the contents of *output undefined.
   bool FindFileByName(const string& filename,
                       protobuf::FileDescriptorProto* output) override;

tools/run_tests/run_interop_tests.py

@@ -759,7 +759,7 @@ def _job_kill_handler(job):
         # When the job times out and we decide to kill it,
         # we need to wait a before restarting the job
         # to prevent "container name already in use" error.
-        # TODO(jtattermusch): figure out a cleaner way to to this.
+        # TODO(jtattermusch): figure out a cleaner way to this.
         time.sleep(2)