DrawingBuffer: Use gfx::GpuMemoryBuffer directly and set color space

content/renderer/renderer_blink_platform_impl.cc

Index: content/renderer/renderer_blink_platform_impl.cc
diff --git a/content/renderer/renderer_blink_platform_impl.cc b/content/renderer/renderer_blink_platform_impl.cc
index 462b14446b039bc4656e610f6db29ec36b305c3a..1da9e4d4109ae47cf6343233bf56d4fb411df678 100644
--- a/content/renderer/renderer_blink_platform_impl.cc
+++ b/content/renderer/renderer_blink_platform_impl.cc
@@ -1085,7 +1085,8 @@ RendererBlinkPlatformImpl::createSharedOffscreenGraphicsContext3DProvider() {
 
 gpu::GpuMemoryBufferManager*
 RendererBlinkPlatformImpl::getGpuMemoryBufferManager() {
-  return RenderThreadImpl::current()->GetGpuMemoryBufferManager();
+  RenderThreadImpl* thread = RenderThreadImpl::current();
+  return thread ? thread->GetGpuMemoryBufferManager() : nullptr;
 }
 
 //------------------------------------------------------------------------------