Revert of [tracing] Display the locked size of discardable memory segment.

content/child/child_discardable_shared_memory_manager.cc

Index: content/child/child_discardable_shared_memory_manager.cc
diff --git a/content/child/child_discardable_shared_memory_manager.cc b/content/child/child_discardable_shared_memory_manager.cc
index 1069fa7242cdf58264d71d7017f7797c9331cb6f..cbe069a27cb011318629a84669ef22ec83331aa7 100644
--- a/content/child/child_discardable_shared_memory_manager.cc
+++ b/content/child/child_discardable_shared_memory_manager.cc
@@ -149,8 +149,6 @@
       continue;
     }
 
-    free_span->set_is_locked(true);
-
     // Memory usage is guaranteed to have changed after having removed
     // at least one span from the free lists.
     MemoryUsageChanged(heap_.GetSize(), heap_.GetSizeOfFreeLists());
@@ -181,7 +179,6 @@
   scoped_ptr<DiscardableSharedMemoryHeap::Span> new_span(heap_.Grow(
       shared_memory.Pass(), allocation_size_in_bytes, new_id,
       base::Bind(&SendDeletedDiscardableSharedMemoryMessage, sender_, new_id)));
-  new_span->set_is_locked(true);
 
   // Unlock and insert any left over memory into free lists.
   if (pages < pages_to_allocate) {
@@ -191,7 +188,6 @@
         leftover->start() * base::GetPageSize() -
             reinterpret_cast<size_t>(leftover->shared_memory()->memory()),
         leftover->length() * base::GetPageSize());
-    leftover->set_is_locked(false);
     heap_.MergeIntoFreeLists(leftover.Pass());
   }
 
@@ -233,11 +229,9 @@
 
   switch (span->shared_memory()->Lock(offset, length)) {
     case base::DiscardableSharedMemory::SUCCESS:
-      span->set_is_locked(true);
       return true;
     case base::DiscardableSharedMemory::PURGED:
       span->shared_memory()->Unlock(offset, length);
-      span->set_is_locked(false);
       return false;
     case base::DiscardableSharedMemory::FAILED:
       return false;
@@ -256,7 +250,6 @@
       reinterpret_cast<size_t>(span->shared_memory()->memory());
   size_t length = span->length() * base::GetPageSize();
 
-  span->set_is_locked(false);
   return span->shared_memory()->Unlock(offset, length);
 }