Expedite discovery of primary DRM device.

content/browser/gpu/gpu_process_host.cc

Index: content/browser/gpu/gpu_process_host.cc
diff --git a/content/browser/gpu/gpu_process_host.cc b/content/browser/gpu/gpu_process_host.cc
index 8329c4ee60fa2dc1b97b2a2c2d55002cdf2e28cb..3a56b8c57b12cb367f7deabbc2dea7e4b83a2b3c 100644
--- a/content/browser/gpu/gpu_process_host.cc
+++ b/content/browser/gpu/gpu_process_host.cc
@@ -82,6 +82,8 @@
 #endif
 
 #if defined(USE_OZONE)
+#include "ui/ozone/public/gpu_platform_support_host.h"
+#include "ui/ozone/public/ozone_platform.h"
 #include "ui/ozone/public/ozone_switches.h"
 #endif
 
@@ -185,6 +187,17 @@ void SendGpuProcessMessage(GpuProcessHost::GpuProcessKind kind,
   }
 }
 
+#if defined(USE_OZONE)
+void SendGpuProcessMessageByHostId(int host_id, IPC::Message* message) {
+  GpuProcessHost* host = GpuProcessHost::FromID(host_id);
+  if (host) {
+    host->Send(message);
+  } else {
+    delete message;
+  }
+}
+#endif
+
 // NOTE: changes to this class need to be reviewed by the security team.
 class GpuSandboxedProcessLauncherDelegate
     : public SandboxedProcessLauncherDelegate {
@@ -596,6 +609,14 @@ bool GpuProcessHost::Init() {
   if (!Send(new GpuMsg_Initialize(gpu_preferences)))
     return false;
 
+#if defined(USE_OZONE)
+  ui::OzonePlatform::GetInstance()

[dnicoara, 2016/11/01 19:00:40]

Is this guaranteed to run before GpuProcessHostUiShim is created?

[hshi1, 2016/11/01 19:06:00]

Yes because GpuProcessHostUiShim::Create() is posted on the UI thread from the
ctor of GpuProcessHost, while GpuProcessHost::Init() is called synchronously on
the IO thread immediately following the ctor of GpuProcessHost in
GpuProcessHost::Get().

+      ->GetGpuPlatformSupportHost()
+      ->OnGpuProcessLaunched(
+          host_id_, BrowserThread::GetTaskRunnerForThread(BrowserThread::IO),
+          base::Bind(&SendGpuProcessMessageByHostId, host_id_));
+#endif
+
   return true;
 }