[tracing] Send smaps file desciptor to child process for tracing

components/tracing/child_memory_dump_manager_delegate_impl.h

Index: components/tracing/child_memory_dump_manager_delegate_impl.h
diff --git a/components/tracing/child_memory_dump_manager_delegate_impl.h b/components/tracing/child_memory_dump_manager_delegate_impl.h
index ca5de293ed7f233cd06dcd286806c8161bd97b08..ba2f3d5142041cf6dc07e26884a12fa308547056 100644
--- a/components/tracing/child_memory_dump_manager_delegate_impl.h
+++ b/components/tracing/child_memory_dump_manager_delegate_impl.h
@@ -10,6 +10,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
 #include "base/synchronization/lock.h"
+#include "components/tracing/tracing_messages.h"
 
 namespace base {
 class SingleThreadTaskRunner;
@@ -38,15 +39,16 @@ class ChildMemoryDumpManagerDelegateImpl
 
   void SetChildTraceMessageFilter(ChildTraceMessageFilter* ctmf);
 
-  // Pass kInvalidTracingProcessId to invalidate the id.
-  void set_tracing_process_id(uint64 id) {
-    DCHECK_IMPLIES(
-        tracing_process_id_ !=
-            base::trace_event::MemoryDumpManager::kInvalidTracingProcessId,
-        id == base::trace_event::MemoryDumpManager::kInvalidTracingProcessId ||
-            id == tracing_process_id_);
-    tracing_process_id_ = id;
-  }
+  // Set the child process tracing id and file descriptors for tracing. This
+  // sets tracing_process_id and sends the file decriptor to relevant dump
+  // providers. ResetMemoryTracingInfo should be called at the end of tracing to
+  // close these files which are not supposed to be used in child if not for
+  // tracing.
+  void SetMemoryTracingInfo(
+      const TracingMsg_MemoryTracingInfo& memory_tracing_info);
+
+  // Resets the tracing process id and resets the relevant dump providers.
+  void ResetMemoryTracingInfo();
 
  protected:
   // Make CreateProcessDump() visible to ChildTraceMessageFilter.