Add xdisplaycheck back until //build dependency is removed

tools/xdisplaycheck/xdisplaycheck.cc

Index: tools/xdisplaycheck/xdisplaycheck.cc
diff --git a/tools/xdisplaycheck/xdisplaycheck.cc b/tools/xdisplaycheck/xdisplaycheck.cc
new file mode 100644
index 0000000000000000000000000000000000000000..6623153a846c06f5d618df5223682e77baff3e90
--- /dev/null
+++ b/tools/xdisplaycheck/xdisplaycheck.cc
@@ -0,0 +1,119 @@
+// 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_(NULL) {}
+  ~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