Send navigation_start to the browser in DidStartProvisionalLoad IPC

content/browser/frame_host/navigation_handle_impl.h

Index: content/browser/frame_host/navigation_handle_impl.h
diff --git a/content/browser/frame_host/navigation_handle_impl.h b/content/browser/frame_host/navigation_handle_impl.h
index 6f46707108e531ceac132639638d387611e5710f..8821dda8d4d17300e55b6441feed910fffcb0bfc 100644
--- a/content/browser/frame_host/navigation_handle_impl.h
+++ b/content/browser/frame_host/navigation_handle_impl.h
@@ -57,9 +57,14 @@ struct NavigationRequestInfo;
 // the RenderFrameHost still apply.
 class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
  public:
+  // |navigation_start| comes from the DidStartProvisionalLoad IPC, which tracks
+  // both renderer-initiated and browser-initiated navigation start.
+  // PlzNavigate: This value always comes from the CommonNavigationParams
+  // associated with this navigation.
   static scoped_ptr<NavigationHandleImpl> Create(
       const GURL& url,
-      FrameTreeNode* frame_tree_node);
+      FrameTreeNode* frame_tree_node,
+      const base::TimeTicks& navigation_start);
   ~NavigationHandleImpl() override;
 
   // NavigationHandle implementation:
@@ -90,6 +95,11 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
       const GURL& new_referrer_url,
       bool new_is_external_protocol) override;
 
+  // The time the navigation started, recorded either in the renderer or browser
+  // process. Corresponds to Navigation Timing API Standard.

[nasko, 2015/11/13 21:52:54]

nit: Drop "Standard".

[Charlie Harrison, 2015/11/14 00:25:00]

Done.

+  // TODO(csharrison) add this to the public class and mark this override.

[nasko, 2015/11/13 21:52:54]

nit: Missing ":" after ). Also, start the comment with capital letter, as it is
a sentence.

[Charlie Harrison, 2015/11/14 00:25:00]

Done.

+  const base::TimeTicks& GetNavigationStart();
+
   NavigatorDelegate* GetDelegate() const;
 
   void set_net_error_code(net::Error net_error_code) {
@@ -162,7 +172,8 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   };
 
   NavigationHandleImpl(const GURL& url,
-                       FrameTreeNode* frame_tree_node);
+                       FrameTreeNode* frame_tree_node,
+                       const base::TimeTicks& navigation_start);
 
   NavigationThrottle::ThrottleCheckResult CheckWillStartRequest();
   NavigationThrottle::ThrottleCheckResult CheckWillRedirectRequest();
@@ -197,6 +208,9 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   // The index of the next throttle to check.
   size_t next_index_;
 
+  // The time this navigation started.
+  const base::TimeTicks navigation_start_;
+
   // This callback will be run when all throttle checks have been performed.
   ThrottleChecksFinishedCallback complete_callback_;