Correctly record and pass around navigation start time.

components/web_view/url_request_cloneable.cc

Index: components/web_view/url_request_cloneable.cc
diff --git a/components/web_view/url_request_cloneable.cc b/components/web_view/url_request_cloneable.cc
index 4ee870aa5f7b7cee5cd6964386401fcfc93390b2..028329eb0ddd4ea7b92f0b24751ee390454e0207 100644
--- a/components/web_view/url_request_cloneable.cc
+++ b/components/web_view/url_request_cloneable.cc
@@ -24,7 +24,9 @@ URLRequestCloneable::URLRequestCloneable(mojo::URLRequestPtr original_request)
       auto_follow_redirects_(original_request->auto_follow_redirects),
       bypass_cache_(original_request->bypass_cache),
       original_body_null_(original_request->body.is_null()),
-      body_(original_request->body.size()) {
+      body_(original_request->body.size()),
+      originating_time_(base::TimeTicks::FromInternalValue(
+          original_request->originating_time_ticks)) {
   // TODO(erg): Maybe we can do some sort of async copy here?
   for (size_t i = 0; i < original_request->body.size(); ++i) {
     mojo::common::BlockingCopyToString(original_request->body[i].Pass(),
@@ -44,7 +46,7 @@ URLRequestCloneable::URLRequestCloneable(const GURL& raw_url)
 
 URLRequestCloneable::~URLRequestCloneable() {}
 
-mojo::URLRequestPtr URLRequestCloneable::Clone() const {
+mojo::URLRequestPtr URLRequestCloneable::Clone() {
   mojo::URLRequestPtr request = mojo::URLRequest::New();
   request->url = url_;
   request->method = method_;
@@ -71,6 +73,13 @@ mojo::URLRequestPtr URLRequestCloneable::Clone() const {
     }
   }
 
+  if (originating_time_.is_null()) {
+    request->originating_time_ticks = base::TimeTicks::Now().ToInternalValue();

[sky, 2015/10/14 22:46:24]

Why do you want to set the time here? If no one supplied a time shouldn't it
remain null?

[yzshen1, 2015/10/14 22:59:16]

When we do back/forward navigation, we clone the original request and use it to
start a new navigation. We want "now" to be the navigation start time.

[sky, 2015/10/14 23:08:36]

Can't the code that clones it reset the time?

[yzshen1, 2015/10/15 00:05:10]

Done.

+  } else {
+    request->originating_time_ticks = originating_time_.ToInternalValue();
+    originating_time_ = base::TimeTicks();
+  }
+
   return request.Pass();
 }