multiple: remove appengine specific build constraints and code (#4685)

Makefile

@@ -41,8 +41,6 @@ vetdeps:
  clean \
  proto \
  test \
- testappengine \
- testappenginedeps \
  testrace \
  vet \
  vetdeps

channelz/service/func_nonlinux.go

@@ -1,4 +1,4 @@
-// +build !linux appengine
+// +build !linux
 
 /*
  *

internal/channelz/types_linux.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

internal/channelz/types_nonlinux.go

@@ -1,4 +1,4 @@
-// +build !linux appengine
+// +build !linux
 
 /*
  *
@@ -37,6 +37,6 @@ type SocketOptionData struct {
 // Windows OS doesn't support Socket Option
 func (s *SocketOptionData) Getsockopt(fd uintptr) {
  once.Do(func() {
- logger.Warning("Channelz: socket options are not supported on non-linux os and appengine.")
+ logger.Warning("Channelz: socket options are not supported on non-linux environments")
  })
 }

internal/channelz/util_linux.go

@@ -1,5 +1,3 @@
-// +build linux,!appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

internal/channelz/util_nonlinux.go

@@ -1,4 +1,4 @@
-// +build !linux appengine
+// +build !linux
 
 /*
  *

internal/channelz/util_test.go

@@ -1,4 +1,4 @@
-// +build linux,!appengine
+// +build linux
 
 /*
  *

internal/credentials/spiffe.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2020 gRPC authors.

internal/credentials/syscallconn.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

internal/credentials/syscallconn_test.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

internal/profiling/buffer/buffer.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2019 gRPC authors.

internal/profiling/buffer/buffer_test.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2019 gRPC authors.

internal/syscall/syscall_linux.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

internal/syscall/syscall_nonlinux.go

@@ -1,4 +1,4 @@
-// +build !linux appengine
+// +build !linux
 
 /*
  *
@@ -35,41 +35,41 @@ var logger = grpclog.Component("core")
 
 func log() {
  once.Do(func() {
- logger.Info("CPU time info is unavailable on non-linux or appengine environment.")
+ logger.Info("CPU time info is unavailable on non-linux environments.")
  })
 }
 
-// GetCPUTime returns the how much CPU time has passed since the start of this process.
-// It always returns 0 under non-linux or appengine environment.
+// GetCPUTime returns the how much CPU time has passed since the start of this
+// process. It always returns 0 under non-linux environments.
 func GetCPUTime() int64 {
  log()
  return 0
 }
 
-// Rusage is an empty struct under non-linux or appengine environment.
+// Rusage is an empty struct under non-linux environments.
 type Rusage struct{}
 
-// GetRusage is a no-op function under non-linux or appengine environment.
+// GetRusage is a no-op function under non-linux environments.
 func GetRusage() *Rusage {
  log()
  return nil
 }
 
 // CPUTimeDiff returns the differences of user CPU time and system CPU time used
-// between two Rusage structs. It a no-op function for non-linux or appengine environment.
+// between two Rusage structs. It a no-op function for non-linux environments.
 func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
  log()
  return 0, 0
 }
 
-// SetTCPUserTimeout is a no-op function under non-linux or appengine environments
+// SetTCPUserTimeout is a no-op function under non-linux environments.
 func SetTCPUserTimeout(conn net.Conn, timeout time.Duration) error {
  log()
  return nil
 }
 
-// GetTCPUserTimeout is a no-op function under non-linux or appengine environments
-// a negative return value indicates the operation is not supported
+// GetTCPUserTimeout is a no-op function under non-linux environments.
+// A negative return value indicates the operation is not supported
 func GetTCPUserTimeout(conn net.Conn) (int, error) {
  log()
  return -1, nil

interop/grpclb_fallback/client.go → interop/grpclb_fallback/client_linux.go

@@ -1,5 +1,3 @@
-// +build linux,!appengine
-
 /*
  *
  * Copyright 2019 gRPC authors.

security/advancedtls/sni.go

@@ -1,4 +1,4 @@
-// +build !appengine,go1.14
+// +build go1.14
 
 /*
  *

security/advancedtls/sni_beforego114.go

@@ -1,4 +1,4 @@
-// +build !appengine,!go1.14
+// +build !go1.14
 
 /*
  *
@@ -26,7 +26,7 @@ import (
 )
 
 // buildGetCertificates returns the first cert contained in ServerOptions for
-// non-appengine builds before version 1.4.
+// builds before version 1.14.
 func buildGetCertificates(clientHello *tls.ClientHelloInfo, o *ServerOptions) (*tls.Certificate, error) {
  if o.IdentityOptions.GetIdentityCertificatesForServer == nil {
  return nil, fmt.Errorf("function GetCertificates must be specified")

vet.sh

@@ -89,10 +89,6 @@ not git grep "\(import \|^\s*\)\"github.com/golang/protobuf/ptypes/" -- "*.go"
 # - Ensure all xds proto imports are renamed to *pb or *grpc.
 git grep '"github.com/envoyproxy/go-control-plane/envoy' -- '*.go' ':(exclude)*.pb.go' | not grep -v 'pb "\|grpc "'
 
-# - Check imports that are illegal in appengine (until Go 1.11).
-# TODO: Remove when we drop Go 1.10 support
-go list -f {{.Dir}} ./... | xargs go run test/go_vet/vet.go
-
 misspell -error .
 
 # - Check that generated proto files are up to date.