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

content/common/gpu/client/context_provider_command_buffer.cc

Index: content/common/gpu/client/context_provider_command_buffer.cc
diff --git a/content/common/gpu/client/context_provider_command_buffer.cc b/content/common/gpu/client/context_provider_command_buffer.cc
index 198fefc7f8d0cd02780c9f86733bcd0cd03b1ad3..be93dc9d636cfd4f55ad31730cd75b369bbab35d 100644
--- a/content/common/gpu/client/context_provider_command_buffer.cc
+++ b/content/common/gpu/client/context_provider_command_buffer.cc
@@ -133,6 +133,11 @@ class GrContext* ContextProviderCommandBuffer::GrContext() {
 
   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();
 }