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

content/gpu/gpu_main.cc

Index: content/gpu/gpu_main.cc
diff --git a/content/gpu/gpu_main.cc b/content/gpu/gpu_main.cc
index 7ffa59e4468e611e614de4026b9e6a2f5f476ae0..d26e90862c878a34103149971c17c9f283ce6c8f 100644
--- a/content/gpu/gpu_main.cc
+++ b/content/gpu/gpu_main.cc
@@ -442,6 +442,11 @@ void GetGpuInfoFromCommandLine(gpu::GPUInfo& gpu_info,
       command_line.GetSwitchValueASCII(switches::kGpuDriverVendor);
   gpu_info.driver_version =
       command_line.GetSwitchValueASCII(switches::kGpuDriverVersion);
+  gpu_info.gpu.active = true;

[Zhenyao Mo, 2016/04/19 21:05:27]

Why assume the primary GPU is active? Wouldn't this be incorrect in some
situations?

[Julien Isorce Samsung, 2016/04/20 17:19:21]

You are right. When there is least one secondary gpu the active gpu will be
identified by gpu::IdentifyActiveGPU (assuming that function succeeds).
gpu::IdentifyActiveGPU will be called from "CollectGraphicsInfo" (some lines
above, i.e. l307)

But when there is no secondary gpu, gpu::IdentifyActiveGPU does an early return
so gpu_info.gpu.active is false (default value). I do not think it is a problem
for black list or workarounds when there is only one gpu but that's is
disturbing that active is false.

I'll change this to set it to true only if gpu_info.secondary_gpus.size() == 0

+  gpu::ParseSecondaryGpuDevicesFromCommandLine(
+      command_line, switches::kGpuSecondaryVendorIDs,
+      switches::kGpuSecondaryDeviceIDs, &gpu_info);
+
   GetContentClient()->SetGpuInfo(gpu_info);
 }