Remove unnecessary instrumentation for several jank bugs.

net/url_request/view_cache_helper.cc

Index: net/url_request/view_cache_helper.cc
diff --git a/net/url_request/view_cache_helper.cc b/net/url_request/view_cache_helper.cc
index 594f7392d9535a22f17ad1d86cfb6094bfe5e659..36d3ae5ce0d89d26b8a422b367c2da11900bb232 100644
--- a/net/url_request/view_cache_helper.cc
+++ b/net/url_request/view_cache_helper.cc
@@ -6,7 +6,6 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
-#include "base/profiler/scoped_tracker.h"
 #include "base/strings/stringprintf.h"
 #include "net/base/escape.h"
 #include "net/base/io_buffer.h"
@@ -363,10 +362,6 @@ int ViewCacheHelper::DoReadDataComplete(int result) {
 }
 
 void ViewCacheHelper::OnIOComplete(int result) {
-  // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
-  tracked_objects::ScopedTracker tracking_profile(
-      FROM_HERE_WITH_EXPLICIT_FUNCTION("422516 ViewCacheHelper::OnIOComplete"));
-
   DoLoop(result);
 }