gpu: Some code cleanups.

services/ui/gpu/gpu_service.cc

Index: services/ui/gpu/gpu_service.cc
diff --git a/services/ui/gpu/gpu_service.cc b/services/ui/gpu/gpu_service.cc
index 6daf6c207927e1d9804c1a31665f197e582e26fd..d9abf74facc74f63adfedbe20e265fac2ca96f7a 100644
--- a/services/ui/gpu/gpu_service.cc
+++ b/services/ui/gpu/gpu_service.cc
@@ -232,8 +232,7 @@ void GpuService::DestroyGpuMemoryBuffer(gfx::GpuMemoryBufferId id,
                               id, client_id, sync_token));
     return;
   }
-  if (gpu_channel_manager_)

[piman, 2017/04/06 20:51:14]

This used to be necessary (in GpuChildThread) because some IPCs could be
pipelined (from the host) after initialization, but initialization could fail
(so we wouldn't create the GpuChannelManager), so the GPU process could see
these messages come in before the process exited.

Is it not possible any more?

[sadrul, 2017/04/07 02:16:12]

We tear-down the mojo connection if the initialization fails [1]. So I think
this should now be safe?

[1]
https://cs.chromium.org/chromium/src/content/gpu/gpu_child_thread.cc?type=cs&...

[piman, 2017/04/07 18:16:41]

Ok. It does rely on the fact that gpu_service_.reset() happens in the same task
as the gpu_service_->Bind(std::move(request)); there. Worth a comment and/or
moving the dead_on_arrival_ path before the Bind.

[sadrul, 2017/04/07 22:57:03]

Sounds good. Moved Bind() to happen after the check for dead_on_arrival_, and
added a comment.

-    gpu_channel_manager_->DestroyGpuMemoryBuffer(id, client_id, sync_token);
+  gpu_channel_manager_->DestroyGpuMemoryBuffer(id, client_id, sync_token);
 }
 
 void GpuService::GetVideoMemoryUsageStats(
@@ -246,10 +245,8 @@ void GpuService::GetVideoMemoryUsageStats(
     return;
   }
   gpu::VideoMemoryUsageStats video_memory_usage_stats;
-  if (gpu_channel_manager_) {
-    gpu_channel_manager_->gpu_memory_manager()->GetVideoMemoryUsageStats(
-        &video_memory_usage_stats);
-  }
+  gpu_channel_manager_->gpu_memory_manager()->GetVideoMemoryUsageStats(
+      &video_memory_usage_stats);
   callback.Run(video_memory_usage_stats);
 }
 
@@ -384,11 +381,6 @@ void GpuService::EstablishGpuChannel(
     return;
   }
 
-  if (!gpu_channel_manager_) {
-    callback.Run(mojo::ScopedMessagePipeHandle());
-    return;
-  }
-
   gpu::GpuChannel* gpu_channel = gpu_channel_manager_->EstablishChannel(
       client_id, client_tracing_id, is_gpu_host);
 
@@ -407,8 +399,6 @@ void GpuService::CloseChannel(int32_t client_id) {
         FROM_HERE, base::Bind(&GpuService::CloseChannel, weak_ptr_, client_id));
     return;
   }
-  if (!gpu_channel_manager_)
-    return;
   gpu_channel_manager_->RemoveChannel(client_id);
 }
 
@@ -418,8 +408,6 @@ void GpuService::LoadedShader(const std::string& data) {
         FROM_HERE, base::Bind(&GpuService::LoadedShader, weak_ptr_, data));
     return;
   }
-  if (!gpu_channel_manager_)
-    return;
   gpu_channel_manager_->PopulateShaderCache(data);
 }
 
@@ -449,8 +437,6 @@ void GpuService::WakeUpGpu() {
     return;
   }
 #if defined(OS_ANDROID)
-  if (!gpu_channel_manager_)
-    return;
   gpu_channel_manager_->WakeUpGpu();
 #else
   NOTREACHED() << "WakeUpGpu() not supported on this platform.";
@@ -469,8 +455,6 @@ void GpuService::DestroyAllChannels() {
         FROM_HERE, base::Bind(&GpuService::DestroyAllChannels, weak_ptr_));
     return;
   }
-  if (!gpu_channel_manager_)
-    return;
   DVLOG(1) << "GPU: Removing all contexts";
   gpu_channel_manager_->DestroyAllChannels();
 }