Add Startup.BrowserView.FirstPaint / .CompositingEnded histograms.

components/startup_metric_utils/browser/startup_metric_utils.h

 // Copyright 2013 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.
 
 #ifndef COMPONENTS_STARTUP_METRIC_UTILS_BROWSER_STARTUP_METRIC_UTILS_H_
 #define COMPONENTS_STARTUP_METRIC_UTILS_BROWSER_STARTUP_METRIC_UTILS_H_
 
 #include "base/time/time.h"
 
 class PrefRegistrySimple;
@@ skipping 12 matching lines @@
 enum class WebContentsWorkload {
   // Only loading a single tab.
   SINGLE_TAB,
   // Loading multiple tabs (of which the profiled WebContents is foreground).
   MULTI_TABS,
 };
 
 // Registers startup related prefs in |registry|.
 void RegisterPrefs(PrefRegistrySimple* registry);
 
-// Returns true if any UI other than the browser window has been displayed
-// so far.  Useful to test if UI has been displayed before the first browser
-// window was shown, which would invalidate any surrounding timing metrics.
-bool WasNonBrowserUIDisplayed();
+// Returns true when browser UI was not launched normally: some other UI was
+// shown first or browser was launched in background mode.
+bool WasMainWindowStartupInterrupted();
 
 // Call this when displaying UI that might potentially delay startup events.
 //
 // Note on usage: This function is idempotent and its overhead is low enough
 // in comparison with UI display that it's OK to call it on every
 // UI invocation regardless of whether the browser window has already
 // been displayed or not.
 void SetNonBrowserUIDisplayed();
 
+// Call this when background mode gets enabled, as it might delay startup
+// events.
+void SetBackgroundModeEnabled();
+
 // Call this with the creation time of the startup (initial/main) process.
-void RecordStartupProcessCreationTime(const base::Time& time);
+void RecordStartupProcessCreationTime(const base::Time time);

[gab, 2017/04/19 18:45:43]

nit: no "const" when passing by value

[themblsha, 2017/04/20 10:42:23]

pkasting did a great explanation why it should be done. Done.

 
 // Call this with a time recorded as early as possible in the startup process.
 // On Android, the entry point time is the time at which the Java code starts.
 // In Mojo, the entry point time is the time at which the shell starts.
-void RecordMainEntryPointTime(const base::Time& time);
+void RecordMainEntryPointTime(const base::Time time);
 
 // Call this with the time when the executable is loaded and main() is entered.
 // Can be different from |RecordMainEntryPointTime| when the startup process is
 // contained in a separate dll, such as with chrome.exe / chrome.dll on Windows.
-void RecordExeMainEntryPointTicks(const base::TimeTicks& time);
+void RecordExeMainEntryPointTicks(const base::TimeTicks time);
 
 // Call this with the time recorded just before the message loop is started.
 // |is_first_run| - is the current launch part of a first run. |pref_service| is
 // used to store state for stats that span multiple startups.
-void RecordBrowserMainMessageLoopStart(const base::TimeTicks& ticks,
+void RecordBrowserMainMessageLoopStart(const base::TimeTicks ticks,
                                        bool is_first_run,
                                        PrefService* pref_service);
 
 // Call this with the time when the first browser window became visible.
-void RecordBrowserWindowDisplay(const base::TimeTicks& ticks);
+void RecordBrowserWindowDisplay(const base::TimeTicks ticks);
 
 // Call this with the time delta that the browser spent opening its tabs.
-void RecordBrowserOpenTabsDelta(const base::TimeDelta& delta);
+void RecordBrowserOpenTabsDelta(const base::TimeDelta delta);
 
 // Call this with a renderer main entry time. The value provided for the first
 // call to this function is used to compute
 // Startup.LoadTime.BrowserMainToRendererMain. Further calls to this
 // function are ignored.
-void RecordRendererMainEntryTime(const base::TimeTicks& ticks);
+void RecordRendererMainEntryTime(const base::TimeTicks ticks);
 
 // Call this with the time when the first web contents loaded its main frame,
 // only if the first web contents was unimpended in its attempt to do so.
-void RecordFirstWebContentsMainFrameLoad(const base::TimeTicks& ticks);
+void RecordFirstWebContentsMainFrameLoad(const base::TimeTicks ticks);
 
 // Call this with the time when the first web contents had a non-empty paint,
 // only if the first web contents was unimpended in its attempt to do so.
-void RecordFirstWebContentsNonEmptyPaint(const base::TimeTicks& ticks);
+void RecordFirstWebContentsNonEmptyPaint(const base::TimeTicks ticks);
 
 // Call this with the time when the first web contents began navigating its main
 // frame. Adds a suffix to its metrics according to |workload|.
-void RecordFirstWebContentsMainNavigationStart(const base::TimeTicks& ticks,
+void RecordFirstWebContentsMainNavigationStart(const base::TimeTicks ticks,
                                                WebContentsWorkload workload);
 
 // Call this with the time when the first web contents successfully committed
 // its navigation for the main frame.
-void RecordFirstWebContentsMainNavigationFinished(const base::TimeTicks& ticks);
+void RecordFirstWebContentsMainNavigationFinished(const base::TimeTicks ticks);
+
+// Call this with the time when the Browser window painted its children for the
+// first time.
+void RecordBrowserWindowFirstPaint(const base::TimeTicks ticks);
+
+// Call this with the time when the Browser window painted its children for the
+// first time and we got a CompositingEnded after that.
+void RecordBrowserWindowFirstPaintCompositingEnded(const base::TimeTicks ticks);
 
 // Returns the TimeTicks corresponding to main entry as recorded by
 // RecordMainEntryPointTime. Returns a null TimeTicks if a value has not been
 // recorded yet. This method is expected to be called from the UI thread.
 base::TimeTicks MainEntryPointTicks();
 
 }  // namespace startup_metric_utils
 
 #endif  // COMPONENTS_STARTUP_METRIC_UTILS_BROWSER_STARTUP_METRIC_UTILS_H_