Dump stats of memory pages which are hooked, but absent from /proc/<pid>/maps.

third_party/tcmalloc/chromium/src/deep-heap-profile.h

Index: third_party/tcmalloc/chromium/src/deep-heap-profile.h
diff --git a/third_party/tcmalloc/chromium/src/deep-heap-profile.h b/third_party/tcmalloc/chromium/src/deep-heap-profile.h
index f820761751dc7a7c454e597ce210c954fe9025c9..4294184d5f101b4730f03c6ffe65f615003c6486 100644
--- a/third_party/tcmalloc/chromium/src/deep-heap-profile.h
+++ b/third_party/tcmalloc/chromium/src/deep-heap-profile.h
@@ -230,6 +230,7 @@ class DeepHeapProfile {
     // Writes stats of the region into |buffer| with |name|.
     void Unparse(const char* name, TextBuffer* buffer);
 
+    size_t virtual_bytes() const { return virtual_bytes_; }
     size_t committed_bytes() const { return committed_bytes_; }
     void AddToVirtualBytes(size_t additional_virtual_bytes) {
       virtual_bytes_ += additional_virtual_bytes;