Instrumenting ReadRawData and InformDelegateDownloadProgress to find jank.

Prior instrumentations showed that:
ReadRawData = 16 jph
InformDelegateDownloadProgress = 4.8 jph

Instrumenting deeper.
The jank in InformDelegateDownloadProgress is a surprise since this method does nothing but posting a task. But still, who knows, and I'm instrumenting it too.

BUG=423948
TBR=jianli@chromium.org, jhawkins@chromium.org, zork@chromium.org, jochen@chromium.org, tzik@chromium.org

Review URL: https://codereview.chromium.org/821073003

Cr-Commit-Position: refs/heads/master@{#309783}

1 files changed, 6 insertions, 0 deletions

diff --git a/content/browser/webui/url_data_manager_backend.cc b/content/browser/webui/url_data_manager_backend.cc
index 9e12864..409e6bd 100644
--- a/content/browser/webui/url_data_manager_backend.cc
+++ b/content/browser/webui/url_data_manager_backend.cc
@@ -17,6 +17,7 @@
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "content/browser/appcache/view_appcache_internals_job.h"
@@ -349,6 +350,11 @@ void URLRequestChromeJob::DataAvailable(base::RefCountedMemory* bytes) {
 
 bool URLRequestChromeJob::ReadRawData(net::IOBuffer* buf, int buf_size,
                                       int* bytes_read) {
+  // TODO(vadimt): Remove ScopedTracker below once crbug.com/423948 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "423948 URLRequestChromeJob::ReadRawData"));
+
   if (!data_.get()) {
     SetStatus(net::URLRequestStatus(net::URLRequestStatus::IO_PENDING, 0));
     DCHECK(!pending_buf_.get());