Do not lose secondary gpus and make sure to have an active gpu on multiple gpu configurations

content/browser/gpu/gpu_data_manager_impl_private.cc

Index: content/browser/gpu/gpu_data_manager_impl_private.cc
diff --git a/content/browser/gpu/gpu_data_manager_impl_private.cc b/content/browser/gpu/gpu_data_manager_impl_private.cc
index ceb4500461f5f1894bab21d64e6f16f4f1220a48..ffc16589e70a301eea483a708b953b746df3f5d7 100644
--- a/content/browser/gpu/gpu_data_manager_impl_private.cc
+++ b/content/browser/gpu/gpu_data_manager_impl_private.cc
@@ -544,6 +544,10 @@ void GpuDataManagerImplPrivate::Initialize() {
       gpu_info.gpu.active = true;
       gpu_info.secondary_gpus.clear();
     }
+
+    gpu::ParseSecondaryGpuDevicesFromCommandLine(
+        *command_line, switches::kGpuTestingSecondaryVendorIDs,
+        switches::kGpuTestingSecondaryDeviceIDs, &gpu_info);
   }
 #if defined(ARCH_CPU_X86_FAMILY)
   if (!gpu_info.gpu.vendor_id || !gpu_info.gpu.device_id) {
@@ -742,6 +746,24 @@ void GpuDataManagerImplPrivate::AppendGpuCommandLine(
       gpu_info_.driver_vendor);
   command_line->AppendSwitchASCII(switches::kGpuDriverVersion,
       gpu_info_.driver_version);
+
+  std::string vendor_ids_str;
+  std::string device_ids_str;
+  for (const auto& device : gpu_info_.secondary_gpus) {
+    if (!vendor_ids_str.empty())
+      vendor_ids_str += ";";
+    if (!device_ids_str.empty())
+      device_ids_str += ";";
+    vendor_ids_str += base::StringPrintf("0x%04x", device.vendor_id);
+    device_ids_str += base::StringPrintf("0x%04x", device.device_id);
+  }
+
+  if (!vendor_ids_str.empty() && !device_ids_str.empty()) {
+    command_line->AppendSwitchASCII(switches::kGpuSecondaryVendorIDs,
+                                    vendor_ids_str);
+    command_line->AppendSwitchASCII(switches::kGpuSecondaryDeviceIDs,
+                                    device_ids_str);
+  }
 }
 
 void GpuDataManagerImplPrivate::UpdateRendererWebPrefs(