Improve memory estimate of SpdySessionPool in net/ MemoryDumpProvider.

net/spdy/spdy_buffer.cc

Index: net/spdy/spdy_buffer.cc
diff --git a/net/spdy/spdy_buffer.cc b/net/spdy/spdy_buffer.cc
index 28e807def4dd1f389a495e6e3edff171d104579d..f75de2f73d416691afe9f74be1d8f56b16814fab 100644
--- a/net/spdy/spdy_buffer.cc
+++ b/net/spdy/spdy_buffer.cc
@@ -10,6 +10,7 @@
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/macros.h"
+#include "base/trace_event/memory_usage_estimator.h"
 #include "net/base/io_buffer.h"
 #include "net/spdy/spdy_protocol.h"
 
@@ -97,6 +98,11 @@ IOBuffer* SpdyBuffer::GetIOBufferForRemainingData() {
   return new SharedFrameIOBuffer(shared_frame_, offset_);
 }
 
+size_t SpdyBuffer::EstimateMemoryUsage() const {
+  // TODO(xunjieli): Estimate |consume_callbacks_|. https://crbug.com/669108.
+  return base::trace_event::EstimateMemoryUsage(shared_frame_->data);
+}
+
 void SpdyBuffer::ConsumeHelper(size_t consume_size,
                                ConsumeSource consume_source) {
   DCHECK_GE(consume_size, 1u);