Thumbnails: Add some perf UMA

chrome/browser/thumbnails/thumbnail_tab_helper.cc

Index: chrome/browser/thumbnails/thumbnail_tab_helper.cc
diff --git a/chrome/browser/thumbnails/thumbnail_tab_helper.cc b/chrome/browser/thumbnails/thumbnail_tab_helper.cc
index a60fd56073a0620a8ad744aa6d319d39906591d1..118d51cd10e376f49cbee01f1d60d3969620f2ef 100644
--- a/chrome/browser/thumbnails/thumbnail_tab_helper.cc
+++ b/chrome/browser/thumbnails/thumbnail_tab_helper.cc
@@ -5,7 +5,7 @@
 #include "chrome/browser/thumbnails/thumbnail_tab_helper.h"
 
 #include "base/feature_list.h"
-#include "build/build_config.h"
+#include "base/metrics/histogram_macros.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/thumbnails/thumbnail_service.h"
 #include "chrome/browser/thumbnails/thumbnail_service_factory.h"
@@ -18,7 +18,6 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host.h"
 #include "content/public/browser/render_widget_host_view.h"
-#include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/scrollbar_size.h"
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(ThumbnailTabHelper);
@@ -41,10 +40,6 @@ class SkBitmap;
 //    may also be captured when a page load finishes (subject to the same
 //    heuristics).
 
-using content::RenderViewHost;
-using content::RenderWidgetHost;
-using content::WebContents;
-
 using thumbnails::ThumbnailingContext;
 using thumbnails::ThumbnailingAlgorithm;
 
@@ -60,23 +55,23 @@ ThumbnailTabHelper::ThumbnailTabHelper(content::WebContents* contents)
   // aren't views like select popups.
   registrar_.Add(this,
                  content::NOTIFICATION_WEB_CONTENTS_RENDER_VIEW_HOST_CREATED,
-                 content::Source<WebContents>(contents));
+                 content::Source<content::WebContents>(contents));
 }
 
-ThumbnailTabHelper::~ThumbnailTabHelper() {
-}
+ThumbnailTabHelper::~ThumbnailTabHelper() = default;
 
 void ThumbnailTabHelper::Observe(int type,
                                  const content::NotificationSource& source,
                                  const content::NotificationDetails& details) {
   switch (type) {
     case content::NOTIFICATION_WEB_CONTENTS_RENDER_VIEW_HOST_CREATED:
-      RenderViewHostCreated(content::Details<RenderViewHost>(details).ptr());
+      RenderViewHostCreated(
+          content::Details<content::RenderViewHost>(details).ptr());
       break;
 
     case content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED:
       if (!*content::Details<bool>(details).ptr())
-        WidgetHidden(content::Source<RenderWidgetHost>(source).ptr());
+        WidgetHidden(content::Source<content::RenderWidgetHost>(source).ptr());
       break;
 
     default:
@@ -84,14 +79,17 @@ void ThumbnailTabHelper::Observe(int type,
   }
 }
 
-void ThumbnailTabHelper::RenderViewDeleted(RenderViewHost* render_view_host) {
+void ThumbnailTabHelper::RenderViewDeleted(
+    content::RenderViewHost* render_view_host) {
   bool registered = registrar_.IsRegistered(
       this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
-      content::Source<RenderWidgetHost>(render_view_host->GetWidget()));
+      content::Source<content::RenderWidgetHost>(
+          render_view_host->GetWidget()));
   if (registered) {
-    registrar_.Remove(
-        this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
-        content::Source<RenderWidgetHost>(render_view_host->GetWidget()));
+    registrar_.Remove(this,
+                      content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
+                      content::Source<content::RenderWidgetHost>(
+                          render_view_host->GetWidget()));
   }
 }
 
@@ -121,12 +119,14 @@ void ThumbnailTabHelper::UpdateThumbnailIfNecessary() {
   // Destroying a WebContents may trigger it to be hidden, prompting a snapshot
   // which would be unwise to attempt <http://crbug.com/130097>. If the
   // WebContents is in the middle of destruction, do not risk it.
-  if (!web_contents() || web_contents()->IsBeingDestroyed())
+  if (!web_contents() || web_contents()->IsBeingDestroyed()) {
     return;
+  }
   // Skip if a pending entry exists. WidgetHidden can be called while navigating
   // pages and this is not a time when thumbnails should be generated.
-  if (web_contents()->GetController().GetPendingEntry())
+  if (web_contents()->GetController().GetPendingEntry()) {
     return;
+  }
   const GURL& url = web_contents()->GetURL();
   Profile* profile =
       Profile::FromBrowserContext(web_contents()->GetBrowserContext());
@@ -146,7 +146,7 @@ void ThumbnailTabHelper::UpdateThumbnailIfNecessary() {
 void ThumbnailTabHelper::AsyncProcessThumbnail(
     scoped_refptr<thumbnails::ThumbnailService> thumbnail_service) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  RenderWidgetHost* render_widget_host =
+  content::RenderWidgetHost* render_widget_host =
       web_contents()->GetRenderViewHost()->GetWidget();
   content::RenderWidgetHostView* view = render_widget_host->GetView();
   if (!view || !view->IsSurfaceAvailableForCopy()) {
@@ -181,6 +181,7 @@ void ThumbnailTabHelper::AsyncProcessThumbnail(
       scale_factor,
       &copy_rect,
       &thumbnailing_context_->requested_copy_size);
+  copy_from_surface_start_time_ = base::TimeTicks::Now();
   view->CopyFromSurface(copy_rect, thumbnailing_context_->requested_copy_size,
                         base::Bind(&ThumbnailTabHelper::ProcessCapturedBitmap,
                                    weak_factory_.GetWeakPtr(), algorithm),
@@ -191,9 +192,14 @@ void ThumbnailTabHelper::ProcessCapturedBitmap(
     scoped_refptr<ThumbnailingAlgorithm> algorithm,
     const SkBitmap& bitmap,
     content::ReadbackResponse response) {
+  base::TimeDelta copy_from_surface_time =
+      base::TimeTicks::Now() - copy_from_surface_start_time_;
+  UMA_HISTOGRAM_TIMES("Thumbnails.CopyFromSurfaceTime", copy_from_surface_time);
+
   if (response == content::READBACK_SUCCESS) {
     // On success, we must be on the UI thread.
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    process_bitmap_start_time_ = base::TimeTicks::Now();
     algorithm->ProcessBitmap(thumbnailing_context_,
                              base::Bind(&ThumbnailTabHelper::UpdateThumbnail,
                                         weak_factory_.GetWeakPtr()),
@@ -209,14 +215,13 @@ void ThumbnailTabHelper::ProcessCapturedBitmap(
   }
 }
 
-void ThumbnailTabHelper::CleanUpFromThumbnailGeneration() {
-  // Make a note that thumbnail generation is complete.
-  thumbnailing_context_ = nullptr;
-}
-
 void ThumbnailTabHelper::UpdateThumbnail(const ThumbnailingContext& context,
                                          const SkBitmap& thumbnail) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  base::TimeDelta process_bitmap_time =
+      base::TimeTicks::Now() - process_bitmap_start_time_;
+  UMA_HISTOGRAM_TIMES("Thumbnails.ProcessBitmapTime", process_bitmap_time);
+
   // Feed the constructed thumbnail to the thumbnail service.
   gfx::Image image = gfx::Image::CreateFrom1xBitmap(thumbnail);
   context.service->SetPageThumbnail(context, image);
@@ -226,19 +231,26 @@ void ThumbnailTabHelper::UpdateThumbnail(const ThumbnailingContext& context,
   CleanUpFromThumbnailGeneration();
 }
 
-void ThumbnailTabHelper::RenderViewHostCreated(RenderViewHost* renderer) {
+void ThumbnailTabHelper::CleanUpFromThumbnailGeneration() {
+  // Make a note that thumbnail generation is complete.
+  thumbnailing_context_ = nullptr;
+}
+
+void ThumbnailTabHelper::RenderViewHostCreated(
+    content::RenderViewHost* renderer) {
   // NOTIFICATION_WEB_CONTENTS_RENDER_VIEW_HOST_CREATED is really a new
   // RenderView, not RenderViewHost, and there is no good way to get
   // notifications of RenderViewHosts. So just be tolerant of re-registrations.
   bool registered = registrar_.IsRegistered(
       this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
-      content::Source<RenderWidgetHost>(renderer->GetWidget()));
+      content::Source<content::RenderWidgetHost>(renderer->GetWidget()));
   if (!registered) {
-    registrar_.Add(this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
-                   content::Source<RenderWidgetHost>(renderer->GetWidget()));
+    registrar_.Add(
+        this, content::NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
+        content::Source<content::RenderWidgetHost>(renderer->GetWidget()));
   }
 }
 
-void ThumbnailTabHelper::WidgetHidden(RenderWidgetHost* widget) {
+void ThumbnailTabHelper::WidgetHidden(content::RenderWidgetHost* widget) {
   UpdateThumbnailIfNecessary();
 }