Fix global dumps to be dumped only when shared memory is actually used

gpu/command_buffer/client/transfer_buffer.cc

Index: gpu/command_buffer/client/transfer_buffer.cc
diff --git a/gpu/command_buffer/client/transfer_buffer.cc b/gpu/command_buffer/client/transfer_buffer.cc
index 161c836c3ae87b3c88d754a045cef24f8bb2e8ee..3c9efadc7b02aaf112aea9b4e494548bf0e094e1 100644
--- a/gpu/command_buffer/client/transfer_buffer.cc
+++ b/gpu/command_buffer/client/transfer_buffer.cc
@@ -195,6 +195,14 @@ unsigned int TransferBuffer::GetMaxAllocation() const {
   return HaveBuffer() ? max_buffer_size_ - result_size_ : 0;
 }
 
+bool TransferBuffer::is_shared() const {
+  if (!HaveBuffer())
+    return false;
+  if (!buffer_->backing())
+    return false;
+  return buffer_->backing()->is_shared();
+}
+
 void ScopedTransferBufferPtr::Release() {
   if (buffer_) {
     transfer_buffer_->FreePendingToken(buffer_, helper_->InsertToken());