Fix bug in virtualized GL context state management upon creation.

gpu/ipc/service/gpu_command_buffer_stub.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/ipc/service/gpu_command_buffer_stub.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 813 matching lines @@
   if (!shared_state_shm->Map(kSharedStateSize)) {
     DLOG(ERROR) << "Failed to map shared state buffer.";
     return false;
   }
   command_buffer_->SetSharedStateBuffer(MakeBackingFromSharedMemory(
       std::move(shared_state_shm), kSharedStateSize));
 
   if (offscreen && !active_url_.is_empty())
     manager->delegate()->DidCreateOffscreenContext(active_url_);
 
+  if (use_virtualized_gl_context_) {
+    // If virtualized GL contexts are in use, then real GL context state
+    // is in an indeterminate state, since the GLStateRestorer was not
+    // initialized at the time the GLContextVirtual was made current. In
+    // the case that this command decoder is the next one to be
+    // processed, force a "full" MakeCurrent to be performed. Note that
+    // GpuChannel's initialization of the gpu::Capabilities expects the
+    // context to be left current.
+    context->ReleaseCurrent(surface_.get());
+    if (!context->MakeCurrent(surface_.get())) {

[jbauman, 2017/05/03 00:53:03]

I think this has to go after "initialized_ = true" or else the state restorer
won't do anything.

+      LOG(ERROR) << "Failed to make context current after initialization.";
+      return false;
+    }
+  }
+
   initialized_ = true;
   return true;
 }
 
 void GpuCommandBufferStub::OnCreateStreamTexture(uint32_t texture_id,
                                                  int32_t stream_id,
                                                  bool* succeeded) {
 #if defined(OS_ANDROID)
   *succeeded = StreamTexture::Create(this, texture_id, stream_id);
 #else
@@ skipping 394 matching lines @@
       command_buffer_->GetLastState().error == error::kLostContext)
     return;
 
   command_buffer_->SetContextLostReason(error::kUnknown);
   if (decoder_)
     decoder_->MarkContextLost(error::kUnknown);
   command_buffer_->SetParseError(error::kLostContext);
 }
 
 }  // namespace gpu