Remove xdisplaycheck

Nothing references the build target, so it should be safe to remove.

xvfb.py now has its own check:
https://source.chromium.org/chromium/chromium/src/+/master:testing/xvfb.py;l=172?q=xvfb.py&ss=chromium
Also we now have xwmstartupcheck, which checks that the WM (openbox)
is running, which implies the X server is up and running.

BUG=1066670

Change-Id: I175df13aef8515e9cc39e0baf8db00c74c6f5cc0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2373175
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Cr-Commit-Position: refs/heads/master@{#801389}

tools/xdisplaycheck/BUILD.gn

-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-executable("xdisplaycheck") {
-  sources = [ "xdisplaycheck.cc" ]
-
-  configs += [ "//build/config/linux:x11" ]
-}

tools/xdisplaycheck/xdisplaycheck.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-//
-// This is a small program that tries to connect to the X server.  It
-// continually retries until it connects or 30 seconds pass.  If it fails
-// to connect to the X server or fails to find needed functiona, it returns
-// an error code of -1.
-//
-// This is to help verify that a useful X server is available before we start
-// start running tests on the build bots.
-
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <time.h>
-#include <X11/Xlib.h>
-
-#if defined(USE_AURA)
-#include <X11/extensions/XInput2.h>
-#endif
-
-void Sleep(int duration_ms) {
-  struct timespec sleep_time, remaining;
-
-  // Contains the portion of duration_ms >= 1 sec.
-  sleep_time.tv_sec = duration_ms / 1000;
-  duration_ms -= sleep_time.tv_sec * 1000;
-
-  // Contains the portion of duration_ms < 1 sec.
-  sleep_time.tv_nsec = duration_ms * 1000 * 1000;  // nanoseconds.
-
-  while (nanosleep(&sleep_time, &remaining) == -1 && errno == EINTR)
-    sleep_time = remaining;
-}
-
-class XScopedDisplay {
- public:
-  XScopedDisplay() : display_(nullptr) {}
-  ~XScopedDisplay() {
-    if (display_) XCloseDisplay(display_);
-  }
-
-  void set(Display* display) { display_ = display; }
-  Display* display() { return display_; }
-
- private:
-  Display* display_;
-};
-
-int main(int argc, char* argv[]) {
-  XScopedDisplay scoped_display;
-  if (argv[1] && strcmp(argv[1], "--noserver") == 0) {
-    scoped_display.set(XOpenDisplay(NULL));
-    if (scoped_display.display()) {
-      fprintf(stderr, "Found unexpected connectable display %s\n",
-              XDisplayName(NULL));
-    }
-    // Return success when we got an unexpected display so that the code
-    // without the --noserver is the same, but slow, rather than inverted.
-    return !scoped_display.display();
-  }
-
-  int kNumTries = 78;  // 78*77/2 * 10 = 30s of waiting
-  int tries;
-  for (tries = 0; tries < kNumTries; ++tries) {
-    scoped_display.set(XOpenDisplay(NULL));
-    if (scoped_display.display())
-      break;
-    Sleep(10 * tries);
-  }
-
-  if (!scoped_display.display()) {
-    fprintf(stderr, "Failed to connect to %s\n", XDisplayName(NULL));
-    return -1;
-  }
-
-  fprintf(stderr, "Connected after %d retries\n", tries);
-
-#if defined(USE_AURA)
-  // Check for XInput2
-  int opcode, event, err;
-  if (!XQueryExtension(scoped_display.display(), "XInputExtension", &opcode,
-                       &event, &err)) {
-    fprintf(stderr,
-        "Failed to get XInputExtension on %s.\n", XDisplayName(NULL));
-    return -2;
-  }
-
-  int major = 2, minor = 0;
-  if (XIQueryVersion(scoped_display.display(), &major, &minor) == BadRequest) {
-    fprintf(stderr,
-        "Server does not have XInput2 on %s.\n", XDisplayName(NULL));
-    return -3;
-  }
-
-  // Ask for the list of devices. This can cause some Xvfb to crash.
-  int count = 0;
-  XIDeviceInfo* devices =
-      XIQueryDevice(scoped_display.display(), XIAllDevices, &count);
-  if (devices)
-    XIFreeDeviceInfo(devices);
-
-  fprintf(stderr,
-      "XInput2 verified initially sane on %s.\n", XDisplayName(NULL));
-#endif
-  return 0;
-}
-
-#if defined(LEAK_SANITIZER)
-// XOpenDisplay leaks memory if it takes more than one try to connect. This
-// causes LSan bots to fail. We don't care about memory leaks in xdisplaycheck
-// anyway, so just disable LSan completely.
-// This function isn't referenced from the executable itself. Make sure it isn't
-// stripped by the linker.
-__attribute__((used))
-__attribute__((visibility("default")))
-extern "C" int __lsan_is_turned_off() { return 1; }
-#endif