tracing: restructure to the components/tracing folder

components/tracing/common/tracing_switches.h

Index: components/tracing/common/tracing_switches.h
diff --git a/components/tracing/tracing_switches.h b/components/tracing/common/tracing_switches.h
similarity index 80%
rename from components/tracing/tracing_switches.h
rename to components/tracing/common/tracing_switches.h
index 388f97be338d3012259ded9a6e09cd0fafb145e1..6d9764b656753d77054a99fbcfd2ad262321e382 100644
--- a/components/tracing/tracing_switches.h
+++ b/components/tracing/common/tracing_switches.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_TRACING_TRACING_SWITCHES_H_
-#define COMPONENTS_TRACING_TRACING_SWITCHES_H_
+#ifndef COMPONENTS_TRACING_COMMON_TRACING_SWITCHES_H_
+#define COMPONENTS_TRACING_COMMON_TRACING_SWITCHES_H_
 
 #include "components/tracing/tracing_export.h"
 
@@ -20,4 +20,4 @@ TRACING_EXPORT extern const char kTraceUploadURL[];
 
 }  // namespace switches
 
-#endif  // COMPONENTS_TRACING_TRACING_SWITCHES_H_
+#endif  // COMPONENTS_TRACING_COMMON_TRACING_SWITCHES_H_