Fixed threading for GPU interface for ArcOemCrypto

This fixes a DCHECK crash where we were making a call to bind the GPU
interface that wasn't called on the IO thread. It now makes a call on
the IO thread to get the interface which then posts a task back to the
original thread to then complete the Mojo call.

Bug: 829045
Test: Verified DCHECK is gone and L1 DRM still works
Change-Id: Ia10ce58a2ecef071f33cfc48a49c72af3bc23a8c
Reviewed-on: https://chromium-review.googlesource.com/998530
Commit-Queue: Jeffrey Kardatzke <jkardatzke@google.com>
Reviewed-by: Luis Hector Chavez <lhchavez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548611}

chrome/browser/chromeos/arc/oemcrypto/arc_oemcrypto_bridge.cc

@@ -14,6 +14,7 @@
 #include "components/arc/arc_bridge_service.h"
 #include "components/arc/arc_browser_context_keyed_service_factory_base.h"
 #include "components/arc/common/protected_buffer_manager.mojom.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/browser/gpu_service_registry.h"
 #include "mojo/edk/embedder/embedder.h"
 #include "mojo/edk/embedder/outgoing_broker_client_invitation.h"
@@ -42,6 +43,14 @@ class ArcOemCryptoBridgeFactory
   ~ArcOemCryptoBridgeFactory() override = default;
 };
 
+mojom::ProtectedBufferManagerPtr GetGpuBufferManagerOnIOThread() {
+  // Get the Mojo interface from the GPU for dealing with secure buffers and
+  // pass that to the daemon as well in our Connect call.
+  mojom::ProtectedBufferManagerPtr gpu_buffer_manager;
+  content::BindInterfaceInGpuProcess(mojo::MakeRequest(&gpu_buffer_manager));
+  return gpu_buffer_manager;
+}
+
 }  // namespace
 
 // static
@@ -133,10 +142,19 @@ void ArcOemCryptoBridge::Connect(mojom::OemCryptoServiceRequest request) {
 
 void ArcOemCryptoBridge::ConnectToDaemon(
     mojom::OemCryptoServiceRequest request) {
-  // Get the Mojo interface from the GPU for dealing with secure buffers and
-  // pass that to the daemon as well in our Connect call.
-  mojom::ProtectedBufferManagerPtr gpu_buffer_manager;
-  content::BindInterfaceInGpuProcess(mojo::MakeRequest(&gpu_buffer_manager));
+  // We need to get the GPU interface on the IO thread, then after that is
+  // done it will run the Mojo call on our thread.
+  base::PostTaskAndReplyWithResult(
+      content::BrowserThread::GetTaskRunnerForThread(content::BrowserThread::IO)
+          .get(),
+      FROM_HERE, base::BindOnce(&GetGpuBufferManagerOnIOThread),
+      base::BindOnce(&ArcOemCryptoBridge::FinishConnectingToDaemon,
+                     weak_factory_.GetWeakPtr(), std::move(request)));
+}
+
+void ArcOemCryptoBridge::FinishConnectingToDaemon(
+    mojom::OemCryptoServiceRequest request,
+    mojom::ProtectedBufferManagerPtr gpu_buffer_manager) {
   oemcrypto_host_daemon_ptr_->Connect(std::move(request),
                                       std::move(gpu_buffer_manager));
 }

chrome/browser/chromeos/arc/oemcrypto/arc_oemcrypto_bridge.h

@@ -41,6 +41,9 @@ class ArcOemCryptoBridge : public KeyedService,
   void OnBootstrapMojoConnection(mojom::OemCryptoServiceRequest request,
                                  bool result);
   void ConnectToDaemon(mojom::OemCryptoServiceRequest request);
+  void FinishConnectingToDaemon(
+      mojom::OemCryptoServiceRequest request,
+      mojom::ProtectedBufferManagerPtr gpu_buffer_manager);
 
   ArcBridgeService* const arc_bridge_service_;  // Owned by ArcServiceManager.
   arc_oemcrypto::mojom::OemCryptoHostDaemonPtr oemcrypto_host_daemon_ptr_;