Bug fix: TranferBufferManager's SharedMemory memory usage reporting was wrong

gpu/command_buffer/common/buffer.cc

Index: gpu/command_buffer/common/buffer.cc
diff --git a/gpu/command_buffer/common/buffer.cc b/gpu/command_buffer/common/buffer.cc
index 8b48b4a45655d194d9359de186953b2c8f601d23..13b606c3286734c4ad04723fd5248239b27143f1 100644
--- a/gpu/command_buffer/common/buffer.cc
+++ b/gpu/command_buffer/common/buffer.cc
@@ -13,6 +13,11 @@
 #include "base/strings/stringprintf.h"
 
 namespace gpu {
+
+bool BufferBacking::is_shared() const {
+  return false;
+}
+
 SharedMemoryBufferBacking::SharedMemoryBufferBacking(
     std::unique_ptr<base::SharedMemory> shared_memory,
     size_t size)
@@ -20,6 +25,10 @@ SharedMemoryBufferBacking::SharedMemoryBufferBacking(
 
 SharedMemoryBufferBacking::~SharedMemoryBufferBacking() {}
 
+bool SharedMemoryBufferBacking::is_shared() const {
+  return true;
+}
+
 void* SharedMemoryBufferBacking::GetMemory() const {
   return shared_memory_->memory();
 }