Add workaround for GPU detection inside a Citrix remote session.

gpu/config/gpu_info_collector_win.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.
 
 #include "gpu/config/gpu_info_collector.h"
 
 // This has to be included before windows.h.
 #include "third_party/re2/src/re2/re2.h"
 
 #include <windows.h>
@@ skipping 332 matching lines @@
   dd.cb = sizeof(DISPLAY_DEVICE);
   std::wstring id;
   for (int i = 0; EnumDisplayDevices(NULL, i, &dd, 0); ++i) {
     if (dd.StateFlags & DISPLAY_DEVICE_PRIMARY_DEVICE) {
       id = dd.DeviceID;
       break;
     }
   }
 
   if (id.length() <= 20) {
-    // Check if it is the RDP mirror driver "RDPUDD Chained DD"
-    if (wcscmp(dd.DeviceString, L"RDPUDD Chained DD") != 0) {
+    // EnumDisplayDevices returns an empty id when called inside a remote
+    // session (unless that session happens to be attached to the console). In
+    // that case, we do not want to fail, as we should be able to grab the
+    // device/vendor ids from the D3D context, below. Therefore, only fail if
+    // the device string is not one of either the RDP mirror driver "RDPUDD
+    // Chained DD" or the citrix display driver.
+    if (wcscmp(dd.DeviceString, L"RDPUDD Chained DD") != 0 &&
+        wcscmp(dd.DeviceString, L"Citrix Systems Inc. Display Driver") != 0) {
       gpu_info->basic_info_state = kCollectInfoNonFatalFailure;
       return kCollectInfoNonFatalFailure;
     }
   }
 
   DeviceIDToVendorAndDevice(id, &gpu_info->gpu.vendor_id,
                             &gpu_info->gpu.device_id);
   // TODO(zmo): we only need to call CollectDriverInfoD3D() if we use ANGLE.
   if (!CollectDriverInfoD3D(id, gpu_info)) {
     gpu_info->basic_info_state = kCollectInfoNonFatalFailure;
@@ skipping 64 matching lines @@
   }
 
   MergeGPUInfoGL(basic_gpu_info, context_gpu_info);
 
   basic_gpu_info->dx_diagnostics_info_state =
       context_gpu_info.dx_diagnostics_info_state;
   basic_gpu_info->dx_diagnostics = context_gpu_info.dx_diagnostics;
 }
 
 }  // namespace gpu