gpu-raster: Check for NULL sk_surface in GpuRasterizer::RasterizeSource.

content/common/gpu/client/context_provider_command_buffer.cc

 // Copyright (c) 2013 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 "content/common/gpu/client/context_provider_command_buffer.h"
 
 #include <set>
 #include <vector>
 
 #include "base/callback_helpers.h"
@@ skipping 115 matching lines @@
 
 class GrContext* ContextProviderCommandBuffer::GrContext() {
   DCHECK(lost_context_callback_proxy_);  // Is bound to thread.
   DCHECK(context_thread_checker_.CalledOnValidThread());
 
   if (gr_context_)
     return gr_context_->get();
 
   gr_context_.reset(
       new webkit::gpu::GrContextForWebGraphicsContext3D(context3d_.get()));
+
+  // If GlContext is already lost, also abandon the new GrContext.
+  if (gr_context_ && IsContextLost())

[piman, 2015/03/09 22:22:05]

nit: no need to test for gr_contex_, it's !NULL here (new asserts rather than
returning NULL).

Should we return NULL rather than an unusable GrContext?

[vmiura, 2015/03/09 22:39:01]

Ok, I'll remove the check.

I think lost context should not cause us to return NULL GrContext as lots of our
code can not handle that case.

[vmiura, 2015/03/09 23:10:01]

Extra NULL check remove Done.

+    gr_context_->OnLostContext();

[no sievers, 2015/03/09 21:25:48]

Can abandonContext() safely be called more than once?

Can we maybe call it directly here?
The OnLostContext() callbacks are usually only called once.

[vmiura, 2015/03/09 21:42:52]

bsalomon@: Is it safe to call abandonContext() more than once?

sievers@: I guess we don't expect ContextProviderCommandBuffer::OnLostCallback()
to be called again after this point.  However I see that
ContextProviderCommandBuffer::VerifyContexts() calls OnLostContext() as well so
if anything was using that, it could happen multiple times.

[vmiura, 2015/03/09 23:10:01]

Calling abandonContext() directly Done.

+
   return gr_context_->get();
 }
 
 void ContextProviderCommandBuffer::SetupLock() {
   DCHECK(context3d_);
   context3d_->GetCommandBufferProxy()->SetLock(&context_lock_);
 }
 
 base::Lock* ContextProviderCommandBuffer::GetLock() {
   return &context_lock_;
@@ skipping 82 matching lines @@
 
 void ContextProviderCommandBuffer::SetMemoryPolicyChangedCallback(
     const MemoryPolicyChangedCallback& memory_policy_changed_callback) {
   DCHECK(context_thread_checker_.CalledOnValidThread());
   DCHECK(memory_policy_changed_callback_.is_null() ||
          memory_policy_changed_callback.is_null());
   memory_policy_changed_callback_ = memory_policy_changed_callback;
 }
 
 }  // namespace content