Use TimeTicks as much as possible in startup_metric_utils.

mandoline/ui/desktop_ui/browser_window.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mandoline/ui/desktop_ui/browser_window.h"
 
 #include "base/command_line.h"
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
@@ skipping 152 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // BrowserWindow, mus::ViewTreeDelegate implementation:
 
 void BrowserWindow::OnEmbed(mus::Window* root) {
   TRACE_EVENT0("desktop_ui", "BrowserWindow::OnEmbed");
   // BrowserWindow does not support being embedded more than once.
   CHECK(!root_);
 
   // Record when the browser window was displayed, used for performance testing.
-  const base::Time display_time = base::Time::Now();
+  const base::TimeTicks display_ticks = base::TimeTicks::Now();
 
   root_ = root;
 
   host_->SetTitle("Mandoline");
 
   content_ = root_->connection()->NewWindow();
   Init(root_);
 
   host_->SetSize(mojo::Size::From(gfx::Size(1280, 800)));
 
@@ skipping 23 matching lines @@
       mus::CreateKeyMatcher(mus::mojom::KEYBOARD_CODE_LEFT,
                             mus::mojom::EVENT_FLAGS_ALT_DOWN));
   host_->AddAccelerator(
       static_cast<uint32_t>(BrowserCommand::GO_FORWARD),
       mus::CreateKeyMatcher(mus::mojom::KEYBOARD_CODE_RIGHT,
                             mus::mojom::EVENT_FLAGS_ALT_DOWN));
   // Now that we're ready, load the default url.
   LoadURL(default_url_);
 
   // Record the time spent opening initial tabs, used for performance testing.
-  const base::TimeDelta open_tabs_delta = base::Time::Now() - display_time;
+  const base::TimeDelta open_tabs_delta =
+      base::TimeTicks::Now() - display_ticks;
 
   // Record the browser startup time metrics, used for performance testing.
   static bool recorded_browser_startup_metrics = false;
   if (!recorded_browser_startup_metrics &&
       base::CommandLine::ForCurrentProcess()->HasSwitch(
           tracing::kEnableStatsCollectionBindings)) {
     mojo::URLRequestPtr request(mojo::URLRequest::New());
     request->url = mojo::String::From("mojo:tracing");
     tracing::StartupPerformanceDataCollectorPtr collector;
     app_->ConnectToService(request.Pass(), &collector);
-    collector->SetBrowserWindowDisplayTime(display_time.ToInternalValue());
+    collector->SetBrowserWindowDisplayTicks(display_ticks.ToInternalValue());
     collector->SetBrowserOpenTabsTimeDelta(open_tabs_delta.ToInternalValue());
-    collector->SetBrowserMessageLoopStartTime(
-        manager_->startup_time().ToInternalValue());
+    collector->SetBrowserMessageLoopStartTicks(
+        manager_->startup_ticks().ToInternalValue());
     recorded_browser_startup_metrics = true;
   }
 }
 
 void BrowserWindow::OnConnectionLost(mus::WindowTreeConnection* connection) {
   root_ = nullptr;
   delete this;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 188 matching lines @@
   omnibox_view_->Embed(view_tree_client.Pass());
 
   // TODO(beng): This should be handled sufficiently by
   //             OmniboxImpl::ShowWindow() but unfortunately view manager policy
   //             currently prevents the embedded app from changing window z for
   //             its own window.
   omnibox_view_->MoveToFront();
 }
 
 }  // namespace mandoline