Revert of cc: Move worker context BindToCurrentThread/SetupLock calls out of cc::OutputSurface.

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 172b1e8720d5681ef32583a7953dbe9435d724cc..ba9f0ebfbed6a6f75196c29a7bf89da933557773 100644
--- a/content/common/gpu/client/context_provider_command_buffer.cc
+++ b/content/common/gpu/client/context_provider_command_buffer.cc
@@ -182,9 +182,7 @@
 }
 
 void ContextProviderCommandBuffer::OnLostContext() {
-  // Note: no thread check here as this should not change the thread for which
-  // this context is currently bound. e.g. a worker context might be unbound
-  // and this should not result in it being bound to the current thread.
+  DCHECK(context_thread_checker_.CalledOnValidThread());
   {
     base::AutoLock lock(main_thread_lock_);
     if (destroyed_)
@@ -199,9 +197,8 @@
 
 void ContextProviderCommandBuffer::OnMemoryAllocationChanged(
     const gpu::MemoryAllocation& allocation) {
-  // Note: no thread check here as this should not change the thread for which
-  // this context is currently bound. e.g. a worker context might be unbound
-  // and this should not result in it being bound to the current thread.
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+
   if (memory_policy_changed_callback_.is_null())
     return;