Convert components/tracing from static lib to component

components/tracing/child_trace_message_filter.h

Index: components/tracing/child_trace_message_filter.h
diff --git a/components/tracing/child_trace_message_filter.h b/components/tracing/child_trace_message_filter.h
index 0686de53c75c2f8e24e0bdc0da18e7dbf8a0adb3..06c276dcb6e0bb0a1894a7ed0f7ea7314c2c87b4 100644
--- a/components/tracing/child_trace_message_filter.h
+++ b/components/tracing/child_trace_message_filter.h
@@ -10,6 +10,7 @@
 #include "base/metrics/histogram.h"
 #include "base/time/time.h"
 #include "base/trace_event/memory_dump_request_args.h"
+#include "components/tracing/tracing_export.h"
 #include "ipc/message_filter.h"
 
 namespace base {
@@ -19,7 +20,7 @@ class SingleThreadTaskRunner;
 namespace tracing {
 
 // This class sends and receives trace messages on child processes.
-class ChildTraceMessageFilter : public IPC::MessageFilter {
+class TRACING_EXPORT ChildTraceMessageFilter : public IPC::MessageFilter {
  public:
   explicit ChildTraceMessageFilter(
       base::SingleThreadTaskRunner* ipc_task_runner);